Firefighters work to put out a fire as white phosphorus exploded after a violent collision when a truck crashed into another vehicle on a highway in Wuhan, central China's Hubei province on April 19, 2013. One of the two truck drivers was killed in the accident while the other succeeded to get out of the truck before the explosion. (Photo by AFP Photo)

A girl cools off in a water basin in Manila on April 19, 2013. The Philippines has been experiencing the hottest days of the year with temperatures of 35 degrees Celsius (95 Fahrenheit) recorded in parts of the city. (Photo by Noel Celis/AFP Photo)

Workers prepare to pull a truck from a sinkhole that opened up on a residential street in the South Deering neighborhood on April 18, 2013 in Chicago, Illinois. The driver of the truck was hospitalized after driving into the 15-feet-deep hole while on his way to work. Two other vehicles were also swallowed by the sinkhole. (Photo by Scott Olson/AFP Photo)

The swearing in of Nicolas Maduro as Venezuela’s new president was interrupted by a man who ran on stage and grabbed the microphone during the inauguration ceremony in Caracas, on April 19, 2013. The man, who tried to appeal for the president’s help, was quickly tackled by bodyguards. The lapse in security was perhaps embarrassing for Maduro, with leaders and dignitaries from around the world attending the event, such as Iran’s president Mahmoud Ahmadinejad. Returning to his speech after the incident, Maduro said: “Security has failed totally. I could easily have been shot. And a comrade, however many ideas he may have, must understand that this is an event that has rules that should be respected”. (Photo by Francisco Boza/AFP Photo)

A Palestinian youth sells corn at a beach in Gaza City during sunset on April 17, 2013 as Palestinians across the West Bank and Gaza Strip marked Prisoners' Day with a series of low-key rallies, as inmates themselves staged a hunger strike. (Photo by Mohammed Abed/AFP Photo)

Teachers members of the National Coordinating Committee of Education Workers (CNTE) march along the highway between Mexico City and Acapulco in Chilpancingo, Guerrero state, Mexico on April 18, 2013. The teachers protest against the educational reform proposed by the government. (Photo by Pedro Pardo/AFP Photo)

A protester gestures in front of an islamic flag during clashes between the Muslim Brotherhood movement's opponents and supporters on April 19, 2013 in central Cairo. Two people were hurt after anti-Islamist protesters marched on thousands of Islamists who had rallied outside the Supreme Court in central Cairo demanding judicial reform. (Photo by Gianluigi Guercia/AFP Photo)

Tree is seen in the middle of thousands used tires in an area of a former recycling company in Lachapelle-Auzac in France, on April 16, 2013. The plant recycling of used tires was closed in 2004, but the tires were not removed. (Photo by Eric Cabanis/AFP Photo)

Picture shows An Garda Siochana carrying out an EU Coordinated Counter Terrorism Exercise, on April 16, 2013. Todays exercise provide the media with an opportunity to witness the challenges faced by law enforcement agencies in responding to terrorist attacks. The irish exercise took place in Dublin and will include police agencies from three other european jurisdictions. (Photo by Leon Farrell/Photocall Ireland)

Firefighter Jason Kelley and police officer Shannon Vandenheuvel carry children from Barbara Jones' partially submerged car in Grand Rapids, Mich. Thursday, April 18, 2013. Middle America was getting everything nature has to throw at it on Thursday, from snow in the north to tornadoes in the Plains, and with torrential rains causing floods and transportation chaos in several states. (Photo by Chris Clark/AP Photo/Grand Rapids Press)

The American Integrity enters the Duluth ship canal after ice on Lake Superior blocked access to the Duluth Superior harbor, causing nine ships to wait at anchor in the open lake until ice breaking operations could open a lane for the traffic, on April 13, 2013. (Photo by Clint Austin/Duluth News Tribune)

Young fans of Canadian singer Justin Bieber attend his concert as part of the “Believe Tour” at Telenor Arena in Fornebu, Norway on April 16, 2013. (Photo by Daniel Sannum Lauten/AFP Photo)

Spectators on the mountains between UTEP and I-10 get a close-up view of the Asarco smokestack demolition in El Paso, Texas, on April 13, 2013. (Photo by Mark Lambie/The El Paso Times)

Actors depicting British troops walk among fallen Colonial Revolutionary War militiamen during the annual Patriot's Day performance of the 1775 Battle of Lexington on the town green in Lexington, Massachusetts, on April 15, 2013. (Photo by Ann Ringwood//MetroWest Daily News)

A Somali girl and her brother run to safety near the scene of a blast in Mogadishu April 14, 2013. At least 16 people were killed as two car bombs exploded outside the law courts in Somalia's capital Mogadishu and gunmen stormed the building on Sunday, before a gunbattle erupted with security forces besieging the compound, witnesses said. (Photo by Feisal Omar/Reuters)

Tibetan Buddhist monks attend a mass prayer in memorial for victims of the earthquake which hit Yushu county three years ago, in Yushu, Qinghai province April 14, 2013. The 7.1-magnitude earthquake that jolted Yushu of northwest China's Qinghai Province three years ago caused 2,698 people dead and 270 missing. Picture taken April 14, 2013. (Photo by Reuters/Stringer)

A South Sudanese model walks along a catwalk wearing a traditional outfit during the Miss World South Sudan contest in Juba, South Sudan, April 13, 2013. The finals of the Miss World contest will take place in September in Indonesia. Picture taken April 13, 2013. (Photo by Andreea Campeanu/Reuters)

A Hindu priest presses his sword against his disciple as they perform a stunt during the annual Shiva Gajan religious festival at Pratapgarh, on the outskirts of the northeastern Indian city of Agartala, April 14, 2013. Hundreds of faithful devotees offer sacrifices and perform acts of devotion during the festival in the hopes of winning the favour of Hindu god Shiva and ensuring the fulfillment of their wishes and also to mark the end of the Bengali calendar year. (Photo by Jayanta Dey/Reuters)

A member of public weeps as the coffin of former British prime minister Margaret Thatcher is transported from St Clement Danes church towards St Paul's Cathedral during her funeral procession, in London April 17, 2013. Thatcher, who was Conservative prime minister between 1979 and 1990, died on April 8 at the age of 87. (Photo by Richard Pohle/Reuters)

Iranian President Mahmoud Ahmadinejad (left) view the Iranian missile during military parade celebrating the country's Army Day in Tehran, on April 18, 2013. (Photo by Hamid Forootan/ISNA)

Women wearing typical Sevillana outfits laugh during the traditional Feria de Abril (April fair) in the Andalusian capital of Seville, southern Spain April 18, 2013. The fair will run until April 21. (Photo by Marcelo del Pozo/Reuters)

A model takes a smoke break at the 7th international festival of hairdressing art, fashion and design called “Crystal Angel” in Kiev, Ukraine, on April 18, 2013. (Photo by Gleb Garanich/Reuters)

Visitors laugh as statue street performers pose as cleaning workers at Fatahilah museum park in Jakarta's old city April 14, 2013. As many as 10 statue performers gather at Fatahilah museum park on weekends to entertain visitors. (Photo by Reuters/Beawiharta)

A visitor reacts as she poses for a photograph in an art installation entitled “You and Me” in Beijing's 798 art area April 18, 2013. (Photo by Jason Lee/Reuters)

A Hindu devotee hanging from a rope throws offering towards other devotees during the “Chadak” ritual in Kolkata April 14, 2013. Hundreds of Hindu devotees attend the ritual, held to worship the Hindu deity of destruction Lord Shiva, on the last day of the Bengali calendar year. (Photo by Rupak De Chowdhuri/Reuters)

A firefighter holds a ladder as people climb down at the site of a hotel fire in Xiangyang, Hubei province, April 14, 2013. At least 11 people have been confirmed dead and 50 others injured in the fire on Sunday morning, Xinhua News Agency reported. (Photo by Reuters/China Daily)

Children play with a huge red ball which is installed outside the Hotel de Ville City Hall as part of the RedBall Project by artist Kurt Perschke in Paris April 19, 2013. The RedBall Project is touring Paris from April 18 to 28, 2013, changing its location each day. (Photo by Charles Platiau/Reuters)

Iranian women attend a mourning ceremony marking the death anniversary of Fatima, the daughter of Islam's Prophet Muhammad, in Tehran, Iran, Sunday, April 14, 2013. (Photo by Ebrahim Noroozi/AP Photo)

A girl, who was previously infected with the H7N9 bird flu virus, talks to the media as she is transferred from the ICU to a public ward at Ditan hospital in Beijing April 15, 2013. According to a hospital spokesperson, the H7N9 virus is no longer detected in the girl's body. Two people in the central Chinese province of Henan have been infected by the new strain of avian influenza, the first cases found in the region, while the death toll has risen to 13 from a total of 60 infections after two more deaths in Shanghai. (Photo by Reuters/Stringer)

A North Korean soldier looks out of the window of a guard tower, on the banks of Yalu River, about 100 km (62 miles) from the North Korean town of Sinuiju, opposite the Chinese border city of Dandong, April 16, 2013. North Korea issued new threats against South Korea on Tuesday, vowing “sledge-hammer blows” of retaliation if South Korea did not apologise for anti-North Korean protests the previous day when the North was celebrating the birth of its founding leader. (Photo by Jacky Chen/Reuters)

A woman lights frankincense as she prays at Shwedagon pagoda on the first day of Myanmar's traditional New Year in Yangon April 17, 2013. (Photo by Soe Zeya Tun/Reuters)

A girl plays inside a giant plastic ball at St. Matthew's fairground, a traditional amusement park, at Holesovice, a suburb in Prague, April 17, 2013. (Photo by David W. Cerny/Reuters)

Traders work on the floor at the New York Stock Exchange, April 17, 2013. (Photo by Brendan McDermid/Reuters)

Elderly women wearing tiaras sit in the audience during a beauty pageant for elderly women called the “Queen of the Elderly” in Guadalajara, Mexico, on April 17, 2013. Eight contestants, ranging in age from 65-75, answered questions about their lives and what it means to be a senior citizen in today's society, as they competed in the annual event to win the top prize of a handbag and jewellery creations by local designers. (Photo by Alejandro Acosta/Reuters)

A devotee takes a holy bath as he offers prayers to the rising sun during the “Astami Snan” festival in the Brahmaputra river at Langalbandh, 20km (12.5 miles) from the capital Dhaka April 18, 2013. Hindus in Bangladesh are celebrating “Astami Snan”, a festival involving a holy bath ritual in the river, which they believe will wash away their sins. (Photo by Andrew Biraj/Reuters)

A paramilitary soldier carries a tent for survivors of an earthquake after unloading it from a helicopter in the town of Mashkeel, southwestern Pakistani province of Baluchistan, near the Iranian border April 18, 2013. The powerful earthquake struck a border area of southeast Iran on Tuesday killing at least 35 people in neighbouring Pakistan, destroying hundreds of houses and shaking buildings as far away as India and Gulf Arab states. (Photo by Naseer Ahmed/Reuters)

Staff take part in a preventive exercise against animal escape in order to enhance its capability of emergency handling at a Zoo in Taiyuan, Shanxi province, China, on April 17, 2013. (Photo by Reuters/China Daily)

Lauryn Mooney, 32, of Boston stands outside the Cathedral of the Holy Cross while United States President Barack Obama was attending an interfaith service for the victims of the Boston Marathon bombings in Boston, Massachusetts April 18, 2013. Obama told a memorial service for the Boston bombing victims that “we will find” whoever carried out the attack that killed three people as investigators search for two men seen on a video of the scene shortly before the blasts. (Photo by Jessica Rinaldi/Reuters)

Russia's Ksenia Afanasyeva competes on the beam during the women's qualifying round of the European Men's and Women's Artistic Gymnastic individual Championships in Moscow April 18, 2013. (Photo by Grigory Dukor/Reuters)

Girls wearing folk costumes participate in the Carnival Benghazi Capital of Culture 2013 in Benghazi, Libya, on April 18, 2013. (Photo by Esam Al-Fetori/Reuters)

Police officers and SWAT team members greet each other after a police assault on a house on Franklin Street in Watertown, Massachusetts April 19, 2013. The manhunt for Dzhokhar Tsarnaev, 19, one of two brothers believed to have carried out the Boston Marathon bombing on Monday ended with his capture while hiding in the stern of a boat parked in the backyard of a house. (Photo by John Taggart/Reuters)

A woman reacts to being soaked by water during a community water fight as part of the Songkran water festival on April 14, 2013 in Bangkok, Thailand. The Songkran festival marks the traditional Thai New Year and is celebrated each year from April 13 to 15. The throwing of water originated as a way to pay respect to people and is meant as a symbol of cleansing and purification. (Photo by Jack Kurtz)

Resident Rosie Meyer, who said she heard gunshots, reacts while watching police respond on April 19, 2013 in Watertown, Massachusetts. After a car chase and shoot out with police, one suspect in the Boston Marathon bombing, Tamerlan Tsarnaev, 26, was shot and killed by police early morning April 19, and a manhunt is underway for his brother and second suspect, 19-year-old suspect Dzhokhar A. Tsarnaev. The two men, reportedly Chechen of origin, are suspects in the bombings at the Boston Marathon on April 15, that killed three people and wounded at least 170. (Photo by Mario Tama)

In attendance at the national launch of the Kellogg’s Cúl Camps 2013 is Dublin footballer Rory O'Carroll, with Paul O'Brien, age 6, from Castleknock, Dublin, and characters Snap, Crackle and Pop. Croke Park, Dublin, on April 16, 2013. (Photo by Brendan Moran)

In this photo released by Indonesian Police, the wreckage of a crashed Lion Air plane sits on the water near the airport in Bali, Indonesia on Saturday, April 13, 2013. The plane carrying more than 100 passengers and crew overshot a runway on the Indonesian resort island of Bali on Saturday and crashed into the sea, injuring nearly two dozen people, officials said. (Photo by AP Photo/Indonesian Police)

Activists dressed as injured orangutans take part in a protest demanding that Indonesian President Susilo Bambang Yudhoyono take immediate action to save the animals in Jakarta, Indonesia, Monday, April 15, 2013. Orangutan populations in Indonesia's Borneo and Sumatera island are facing severe threats from habitat loss, illegal logging, fires and poaching. (Photo by Tatan Syuflana/Associated Press)

Egyptian protesters clash near a bus belonging to Muslim Brotherhood supporters burns after it was reportedly set alight by anti- government protesters in Cairo, Egypt, Friday, April 19, 2013. Clashes erupted Friday between several hundred opponents and supporters of Egypt’s Islamist president during a rally by his allies calling on him to “cleanse the judiciary” of alleged supporters of the old regime. (Photo by Mostafa Elshemy/AP Photo)

Spain's Rafael Nadal serves the ball to Marinko Matosevic of Australia during their match of the Monte Carlo Tennis Masters tournament in Monaco, on April 17, 2013. (Photo by Lionel Cironneau/Associated Press)

Lauren Vincent, fundraising manager for Gromit Unleashed, poses on April 19, 2013 with four, of around 70, Gromit sculptures painted by (left to right) Sir Paul Smith, Cath Kidston, Richard Williams and Simon Tofield, at a secret location in Bristol before they are placed for public view on an arts trail around the city from July 1st. After the public arts trail the sculptures will be auctioned to raise funds for Wallace and Gromit's Grand Appeal's campaign to raise funds for the expansion of Bristol Children's Hospital. (Photo by Tim Ireland/PA Wire)

A South Korean soldier runs by a billboard during an anti-terror drills at Government Complex in Sejong South Korea, on April 17, 2013. (Photo by Lee Jin-man/Associated Press)

South Korean protesters wearing masks made out of envelopes displaying the flags of the United States, North Korea and South Korea, participate in a rally to mark Global Day of Action on Military Spending near the U.S. Embassy in Seoul, South Korea, on April 15, 2013. (Photo by Ahn Young-joon/Associated Press)

A model wears a creation from the Cantao summer collection during Fashion Rio in Rio de Janeiro, Brazil, on April 17, 2013. (Photo by Felipe Dana/Associated Press)

Phil Williams from Chester holds a banner outside the Courts of Justice in the Strand prior to the funeral service of Baroness Thatcher at St Paul's Cathedral, central London, on April 17, 2013. (Photo by Joe Giddens/PA Wire)

Police patrol through a neighborhood in Watertown while searching for Dzhokar Tsarnaev, on April 19, 2013. (Photo by Charles Krupa/Associated Press)

An activist of Jammu Kashmir Liberation Front (JKLF) shouts as Indian police detain him during a protest in Srinagar, India, Friday, April 19, 2013. Indian police detained nearly a dozen of JKLF activists during a protest demanding the return of the body of a Kashmiri man Mohammed Afzal Guru who was secretly executed and buried in the Indian capital. Kashmir was rocked by violent anti-India protests after Guru was hanged in a New Delhi jail on February 9. He was convicted of involvement in a 2001 attack on India's Parliament. (Photo by Dar Yasin/AP Photo)

A police officer in Boston reacts to news of the arrest of Dzhokhar Tsarnaev, on April 19, 2013. (Photo by Julio Cortez/Associated Press)

Former Bagram and Guantanamo Bay prisoners dressed in orange prison uniforms,demand the release of Yemeni detainees in the Guantanamo Bay prison as they protest in front of the US Embassy in Sanaa, Yemen, on April 16, 2013. (Photo by Hani Mohammed/Associated Press)

A passenger sleeps in a subway train in Seoul, South Korea Friday, April 19, 2013. (Photo by Kin Cheung/AP Photo)

Previously unissued photo dated April 19, 2013 of a view of part of the CMS detector at the Large Hadron Collider, at the European Organization for Nuclear Research, known as CERN in Meyrin, Switzerland. Scientists are switching to the Dark Side as they prepare to ramp up the power at the Large Hadron Collider (LHC). After capturing a species of Higgs boson, the particle hunters now have their sights set on a new trophy – dark matter. A race is on between groups at the LHC, the world s biggest particle accelerator, and other scientists operating in space and deep underground who are chasing the same discovery. (Photo by John Von Radowitz/PA Wire)

Red stage lighting shine on a group of North Korean children while they sing during a performance at Mangyongdae Children's Palace in Pyongyang, North Korea, on April 18, 2013. (Photo by Alexander F. Yuan/Associated Press)

A cyclist pedals past a sculpture at the golden sea beach in Puri, India, with a message against terrorism following attacks in Boston and Bangalore, on April 17, 2013. (Photo by Associated Press)

South Korean Army soldiers ride a K-1 tank during an annual military exercise in Paju near the border village of the Panmunjom, South Korea, Friday, April 19, 2013. North Korea on Thursday demanded the withdrawal of U.N. sanctions and the end of U.S.-South Korea military drills as conditions for resuming talks meant to defuse tension on the Korean Peninsula. (Photo by Ahn Young-joon/AP Photo)

Former U.S. president George Bush, father of George W. Bush poses with new cheerleaders of the football team Houston Texans, in Houston, Texas, on April 18, 2013. (Photo by Smiley N. Pool/AP Photo/Houston Chronicle)

A man dressed as the Hindu Goddess Kali participates in a religious procession as part of the “Ram Navami” festival in New Delhi, India, on April 19, 2013. Ram Navami celebrates the birthday of Hindu god Rama. (Photo by Kevin Frayer/Associated Press)

British forces carry a Union Jack-draped coffin outside St. Paul's Cathedral in central London during the rehearsal for the upcoming funeral of former British Prime Minister Margaret Thatcher on Wednesday, April 15, 2013. (Photo by Lefteris Pitarakis/Associated Press)

A boy blows fire during a religious procession in Amritsar, India, to celebrate the birthday of the Hindu god Rama, on April 19, 2013. (Photo by Sanjeev Syal/Associated Press)

A man calls for help to extinguish a fire reported to be set by black block protesters on a bus belonging to Muslim Brotherhood supporters in Cairo, on April 19, 2013. Several hundred supporters and opponents of Egypt's President Mohammed Morsi clashed near Cairo's Tahrir Square amid a rally calling on Morsi to “cleanse the judiciary”. (Photo by Amr Nabil/Asociated Press)

Sunderland's manager Paolo Di Canio celebrates after Stephane Sessegnon scores his goal during their English Premier League soccer match against Newcastle United at St James' Park, Newcastle, England, on April 14, 2013. (Photo by Scott Heppell/Associated Press)

87-year-old Nazi concentration camp survivor Petro Mischtschuk, from Ukraine, reacts during the commemoration ceremonies for the 68th anniversary of the liberation of the Buchenwald concentration camp near Weimar, Germany, on April 14, 2013. (Photo by Jens Meyer/Associated Press)

A volunteer helps to clean a Jewish cemetery in Warsaw, on April 14, 2013. Volunteers are answering a call by Polish officials to help clean the Okopowa Street Jewish Cemetery as the city launches a month of commemorative events marking the 70th anniversary of the Warsaw Ghetto Uprising. The events come amid a growing inclination in Poland to celebrate the country’s Jewish history. (Photo by Czarek Sokolowski/Associated Press)

Villagers run on burning charcoal as they perform a ritual during the Jhamu festival on the outskirts of Bhubaneswar, India, on April 14, 2013. The festival marks the beginning of the Oriya New Year. (Photo by Biswaranjan Rout/Associated Press)

A boy uses his mouth to get a chip from a plastic basin filled with powder during the “OlymPEACE” games at Camp Aguinaldo, in suburban Quezon city, north of Manila, on April 14, 2013. The event aims to educate children to appreciate the value of peace. (Photo by Aaron Favila/Associated Press)

Fireworks explode during the official opening of the renovated Rijksmuseum in Amsterdam, Netherlands, on April 13, 2013. The Rijksmuseum, home of Rembrandt's “The Night Watch” and other national treasures, reopensed its doors to the public after a decade-long renovation. (Photo by Peter Dejong/Associated Press)

Models show their nails to jury members, behind a wall, during the 6th German Nailart-Trophy “Circus, Magic – Manege” at the BEAUTY FORUM and trade fair in Leipzig, on April 13, 2013. The event is one of the most important cosmetic trade fairs in Germany. (Photo by Jens Meyer/Associated Press)

Bodypainter Johannes Stoetter of Italy, works on his model during the 6th Bodypainting Trophy competition at the BEAUTY FORUM and trade fair in Leipzig, on April 13, 2013. (Photo by Jens Meyer/Associated Press)

An anti-government protester wears a mask of jailed human rights activist Nabeel Rajab, during clashes with police in Qadam, Bahrain, on April 19, 2013. Clashes between protesters and police continued Friday ahead of Sunday's Formula One Grand Prix. Hardline protesters hope to embarrass the ruling royal family with increased violence, while more moderate protesters, who support the race, merely want to highlight their demands for a greater voice in the country. (Photo by Hasan Jamali/Associated Press)

A rescue official stands with a motorist stuck in water during heavy rains and flooding in Round Lake Heights, Illinois, Thursday, April 18, 2013, at Pontiac Court and Tomahawk Trail. (Photo by Joe Shuman/Chicago Tribune/MCT)

People comfort one another during a candle light vigil at St. Mary, Church of the Assumption for victims, families, friends and first responders involved with the recent fertilizer plant explosion, Thursday April 18, 2013 in West, Texas. (Photo by Ron Jenkins/AP Photo/The Fort Worth Star-Telegram)

A policeman comforts a man next to the body of Maria Duron, a pregnant fruit vendor caught in the crossfire after gunmen opened fire on a vehicle, killing a sixteen year-old student, her police bodyguard and three other people who were on the street in the city of Tegucigalpa, Honduras, on April 15, 2013. (Photo by Fernando Antonio/Associated Press)

The Solar Impulse lands during a test flight at Moffett Field NASA Ames Research Center in Mountain View, Calif., Friday, April 19, 2013. A solar-powered plane that has wowed aviation fans in Europe is set to take an early morning test flight over the San Francisco Bay area. Considered the world's most advanced sun-powered plane, the Solar Impulse is set to take off from Moffett Field in Mountain View at first light for a two-hour practice run leading up to the start of a multi-city, cross-country tour. (Photo by Jeff Chiu/AP Photo)

Iranian army troops march in a parade marking National Army Day in front of the mausoleum of the late revolutionary founder Ayatollah Khomeini, just outside Tehran, Iran, on April 17, 2013. (Photo by Vahid Salemi/Associated Press)

Milwaukee Brewers' Carlos Gomez ducks out of the way as teammate Ryan Braun tries to dunk him with water after beating the San Francisco Giants 4-3, on April 17, 2013. (Photo by Morry Gash/Associated Press)

A boy jumps over a barricade of burning garbage that supporters of opposition leader Henrique Capriles used to block a street, as they demonstrated for a recount of the votes in Sunday's election, in Caracas, April 15, 2013. Hundreds of protesters clashed with police in the Venezuelan capital on Monday after Capriles called for demonstrations to demand a recount of votes from Sunday's election to replace the late Hugo Chavez. (Photo by Tomas Bravo/Reuters)