A large tree is seen resting on a car after a tornado struck on Monday, on April 30, 2014 in Tupelo, Mississippi. Deadly tornadoes ripped through the region over the last days, leaving more than a dozen dead. (Photo by Joe Raedle/AFP Photo)

Sri Lankan residents look at derailed carriges after two trains collided in Pothuhera, about 90 kilometers (56 miles) northeast of Colombo on April 30, 2014. At least 68 passengers were injured in the train accident at Pothuhera, police said. (Photo by AFP Photo)

Columbia team rider Columbian Andres Torres Agudelo (L) and Omega Pharma Quick Step team rider Carlos Verona of Spain (R) recover after they crashed with Lampre Merida team rider portuguese Rui Alberto Faria Da Costa (back) during the Liege Bastogne Liege cycling race from Liege to Ans, Belgium, 27 April 2014. (Photo by Nicolas Bouvy/EPA)

Former Tunisian Femen activist Amina Sboui (R) gestures as obscenely as two other bare-chested women shout slogans outside the Egyptian embassy in Paris on April 30, 2014 during a demonstration against death sentences handed by an Egyptian court to 683 alleged Islamists. Slogan in Arabic on Sboui's body reads “No to death sentences even for the Muslim Brotherhood”. (Photo by Eric Feferberg/AFP Photo)

A competitor performs in the FMX Course competition during the World Extreme Games in Shanghai April 30, 2014. The games will be held in Shanghai until May 3. (Photo by Carlos Barria/Reuters)

A sub-Saharan migrant agues with a Spanish Guardia Civil officer holding a baton, as they sit on top of a metallic fence that divides Morocco and the Spanish enclave of Melilla, Thursday, May 1, 2014. Spain says around 700 African migrants have rushed its barbed wire border fences in the North African enclave of Melilla, and although police repelled most, 140 managed to enter Spanish territory. The migrants charged the fences in two waves, with 500 arriving in the early hours and another 200 later Thursday morning. Spain and Morocco stepped up border vigilance in February when 15 migrants drowned trying to enter Spain's other north African coastal enclave, Ceuta. (Photo by Fernando Garcia/AP Photo)

Ukrainian government troops patrol on a country road outside the town of Svyitohirsk near to Slovyansk, eastern Ukraine, Saturday, April 26, 2014. Ukrainian authorities are undertaking a security operation to liberate the nearby city of Slovyansk, which is currently controlled by an armed pro-Russian insurgency. (Photo by Alexander Zemlianichenko/AP Photo)

U.S. military soldiers using their smartphones take pictures of U.S. President Barack Obama after delivering a speech at U.S. military base Yongsan Garrison in Seoul, South Korea, Saturday, April 26, 2014. (Photo by Lee Jin-man/AP Photo)

Armed men guard at the Kombikorm factory checkpoint, near Svyatogorsk town close to Slaviansk, Ukraine, 30 April 2014. Militants in Sloviansk are keeping dozens of hostages, including seven European military observers, who were detained in the city on 25 April while on a verification mission under the Organisation of Security and Cooperation in Europe (OSCE). (Photo by Igor Kovalenko/EPA)

Members of activist Party List group “Akbayan” wearing picture cut-out masks of U.S. President Barack Obama and China's President Xi Jinping make a "selfie" with a mobile phone in a coffee shop in Quezon city, Metro Manila April 27, 2014. Members of Akbayan Youth sat down inside a coffee shop wearing Xi and Obama masks while sipping coffee with each other as a creative symbolization of the two superpower's struggle for power in the Asia-Pacific region, a day ahead of a scheduled state visit by Obama. (Photo by Erik De Castro/Reuters)

Riot policemen clash with fans prior to the cup final between Athens's Panathinaikos and Thessalonikis's PAOK at the Olympic Stadium in Athens, Greece Saturday, April 26 2014. More than 300 buses carrying PAOK supporters from the northern Greek city of Thessaloniki were stopped by police at a toll station 34 kilometers (21 miles) north of the capital Athens. The supporters were searched and allowed to proceed, 20 buses at a time, to the Athens Olympic Stadium, where the Greek Cup final between soccer clubs PAOK and Panathinaikos is taking place. Police, fearing clashes between rival fans, has been directing supporters to different gates of the stadium several hours before the game's start at 8 p.m. local. (Photo by Kostas Tsironis/AP Photo)

Children wearing Pope's cassocks ride a Popemobile that was used by Pope John Paul II in his 1995 visit to Manila, during a parade in Quezon city, Metro Manila April 27, 2014. Pope John XXIII, who reigned from 1958 to1963 and called the modernising Second Vatican Council, and Pope John Paul II, who reigned for nearly 27 years before his death in 2005 and whose trips around the world made him the most visible pope in history, will be declared saints by Pope Francis at an unprecedented twin canonisation on Sunday. (Photo by Erik De Castro/Reuters)

A country music fan cools off in the wind on the second day of the Stagecoach country music festival in Indio, California April 26, 2014. (Photo by Mike Blake/Reuters)

An anti-government protester takes part in a march against education reforms in Caracas April 26, 2014. Venezuelan justice determined on Friday that Venezuelans who want peaceful protest must request permission from local governments to prevent the scattered forces, amid a wave of violent protests against President Nicolas Maduro. (Photo by Christian Veron/Reuters)

Protesters shield themselves as riot police fires tear gas during a May Day demonstration in Istanbul May 1, 2014. Turkish police fired water cannon and tear gas on Thursday to prevent hundreds of protesters from defying a ban on May Day rallies and reaching Istanbul's central Taksim Square, the focal point of weeks of protests last summer. (Photo by Murad Sezer/Reuters)

Catholic priests hold a mass during the canonization of Pope John Paul II and Pope John XXIII in Kasprowy Wierch, in Poland’s Tatra mountains, on April 27, 2014. Pope Francis proclaimed his predecessors John XXIII and John Paul II saints on Sunday, hailing both as courageous men who withstood the tragedies of the 20th century. (Photo by Marek Podmokly/Agencja Gazeta via Reuters)

Zoltan Veres of Hungary flies with his MXS airplane under Budapest's Chain Bridge during an air show, May 1, 2014. (Photo by Laszlo Balogh/Reuters)

Pro-Russian (R) and pro-Ukrainian supporters clash during a pro-Ukrainian rally in Donetsk, eastern Ukraine April 28, 2014. Several people were wounded when pro-Russian separatists attacked a rally in support of Ukrainian unity in the separatist-held city of Donetsk in eastern Ukraine on Monday. (Photo by Baz Ratner/Reuters)

Revelers dance on a street during the Jamaica Carnival Roadmarch in Kingston, Jamaica, on April 27, 2014. The Roadmarch is the final day of the festivities of the Carnival season. (Photo by Gilbert Bellamy/Reuters)

People dressed as blocks of currency notes as part of a marketing campaign walk in Moscow April 28, 2014. (Photo by Sergei Karpukhin/Reuters)

An employee poses with “The Blue” diamond at Christie's auction house in London April 29, 2014. Christie's London is displaying the largest flawless fancy vivid blue diamond ever to appear at auction. The diamond is pegged at $21 million to $25 million and is the highlight of an upcoming Magnificent Jewels sale in Geneva. (Photo by Stefan Wermuth/Reuters)

A pro-Russian protester walks in front of riot police during a pro-Ukraine rally in the eastern city of Donetsk April 28, 2014. Several people were wounded when what appeared to be stun grenades exploded during a rally in support of Ukrainian unity in the eastern, separatist-held city of Donetsk on Monday, a Reuters reporter said. (Photo by Marko Djurica/Reuters)

Pro-Russian protesters attack a pro-Ukrainian protester during a rally in the eastern city of Donetsk, on April 28, 2014. Several people were wounded when what appeared to be stun grenades exploded during a rally in support of Ukrainian unity in the eastern, separatist-held city of Donetsk, Reuters reported. (Photo by Marko Djurica/Reuters)

A woman passes her child on the top of a truck during a break from her journey towards Chad's border escorted by African Union operation in CAR (MISCA) a few kilometres after the northern town of Kaga Bandoro April 29, 2014. Of the remaining Muslims that have been sheltered from sectarian violence in the neighbourhood of PK12 in Bangui, over one thousand have been evacuated towards the northern town of Kabo and Sido on the border with Chad. (Photo by Siegfried Modola/Reuters)

Russian military vehicles drive down Tverskaya Street in central Moscow on April 29, 2014, during rehearsals for the Victory Day military parade, which is held every year on May 9 to mark Russia’s victory over Nazi Germany in World War II. (Photo by Maxim Shemetov/Reuters)

Workers install a demilitarized Soviet-made T-62M1 tank at a memorial in a park in Russia's Siberian city of Krasnoyarsk April 30, 2014. (Photo by Ilya Naymushin/Reuters)

A gust of wind blows off Pope Francis' cap during his weekly general audience at St. Peter's Square at the Vatican April 30, 2014. (Photo by Alessandro Bianchi/Reuters)

Andreas Strauss poses at “Dasparkhotel” hotel rooms in a public park in the Upper Austrian town of Ottensheim April 29, 2014. The rooms are constructed from repurposed concrete drain pipes and can be booked anonymously on the internet. Owner Strauss says the hotel is a hospitality project on a “pay as you wish” basis, a system where customers pay what they can afford. The hotel is open from May 1 till October 1. (Photo by Heinz-Peter Bader/Reuters)

A person tries to break the window of a destroyed truck in Vilonia, Ark., on April 30, 2014. Severe floods in Florida’s Panhandle and coastal Alabama deluged roads and engulfed homes and cars on Wednesday. (Photo by Carlo Allegri/Reuters)

Michael Stanek hugs his daughter Kennedy Stanek as they take a break from helping friends sift though the rubble of their homes in Vilonia, Arkansas April 30, 2014. Severe floods in Florida's Panhandle and coastal Alabama deluged roads and engulfed homes and cars on Wednesday, the latest mayhem created by a tornado-packing storm system that has killed at least 34 people in the United States this week. (Photo by Carlo Allegri/Reuters)

A model waits as Russian artist Vasily Slonov (R) adjusts a work called “Kremlin from military” on a war monument near Russia's Siberian city of Krasnoyarsk, May 2, 2014. Slonov produced the “Great Russia” collection of art iron headwear styled after a Kokoshnik, the traditional Russian female headdress. Slonov is preparing to show the work in Riga. (Photo by Ilya Naymushin/Reuters)

Kylie Wicker tries on a prosthetic hand at Boylan Catholic High School in Rockford, Illinois, May 2, 2014. The Engineering Graphics class at the school took on the project of making a prosthetic hand for Wicker, who was born without fingers on her left hand, using a 3-D printer and instructions that were posted on the internet. (Photo by Jim Young/Reuters)

Ukrainian Interior Ministry security forces, blocked by pro-Russian activists, gather outside the regional government headquarters in Luhansk, eastern Ukraine, April 29, 2014. Hundreds of pro-Russian separatists stormed the regional government headquarters in Ukraine's eastern city of Luhansk on Tuesday, gaining access by breaking windows and facing no resistance from police. (Photo by Vasily Fedosenko/Reuters)

Michael Norris of Australia performs during a presentation of the World Extreme Games in Shanghai April 27, 2014. The games will be held in Shanghai from April 30 to May 3. (Photo by Carlos Barria/Reuters)