A relative carries a picture of a student killed in Thursday's attack by gunmen, at the Chiromo Mortuary in Kenya's capital Nairobi April 6, 2015. The Kenyan air force has destroyed two al Shabaab camps in Somalia, it said on Monday, in the first major military response since the Islamist group massacred students at a Kenyan university last week. (Photo by Thomas Mukoya/Reuters)

A Kenyan holds a candle and flowers as she listens to the names of each of the victims of the Garissa attack being read out aloud, during a vigil at Uhuru Park in Nairobi, Kenya Tuesday, April 7, 2015. Students and other Kenyans gathered at dusk to honor and remember the victims, lighting candles, holding flowers, reading their names aloud, and erecting a white wooden cross for each of those who were killed in the Garissa University College attack. (Photo by Ben Curtis/AP Photo)

Kenyan university students participate in a demonstration against an attack by gunmen at the Garissa University College campus, along the streets of the capital Nairobi, April 7, 2015. (Photo by Thomas Mukoya/Reuters)

A group of students and other Kenyans sit around white roses and candles and discuss the recent attack in Garissa, as they wait for a vigil at Uhuru Park in Nairobi, Kenya Tuesday, April 7, 2015. (Photo by Ben Curtis/AP Photo)

Kenyans hold candles and flowers as they listen to the names of each of the victims of the Garissa attack being read out aloud, during a vigil at Uhuru Park in Nairobi, Kenya Tuesday, April 7, 2015. (Photo by Ben Curtis/AP Photo)

Kenyan university students participate in a demonstration against an attack by gunmen at the Garissa University College campus, along the streets of the capital Nairobi, April 7, 2015. (Photo by Goran Tomasevic/Reuters)

A man plays an accordion during a prayer session following an attack by gunmen at the Garissa University College campus, along the streets of the capital Nairobi, April 7, 2015. (Photo by Thomas Mukoya/Reuters)

A woman carries a rose as she arrives for a memorial vigil for the people killed by gunmen at Garissa University College, at the “Freedom Corner” in Nairobi April 7, 2015. (Photo by Goran Tomasevic/Reuters)

A goat named “White On The Right” bleats as it is paraded with other goats prior to a race during the annual Easter goat racing event at the Mount Pleasant recreation ground in Tobago April 6, 2015. (Photo by Andrea De Silva/Reuters)

Goats and their jockeys jostle for position as they participate in a race during the annual Easter goat racing event at the Mount Pleasant recreation ground in Tobago April 6, 2015. (Photo by Andrea De Silva/Reuters)

Firefighters look on as they try to extinguish a fire at a petrochemical plant in Zhangzhou, Fujian province April 7, 2015. At least six people were injured after an explosion hit part of an oil storage facility on Monday at Dragon Aromatics, an independent petrochemical producer in eastern China, Xinhua reported. The blast happened around 7 p.m. (11:00 GMT) at a pumping station for a condensate storage at the plant in Zhangzhou in Fujian province that produces paraxylene, or PX, a chemical used in making polyester fibre and plastics, state media said. (Photo by Reuters/Stringer)

Firefighters try to extinguish a fire at a petrochemical plant in Zhangzhou, Fujian province April 7, 2015. (Photo by Reuters/Stringer)

Firefighters try to extinguish a fire at a petrochemical plant in Zhangzhou, Fujian province April 7, 2015. (Photo by Reuters/Stringer)

Firefighters try to extinguish a fire at a petrochemical plant in Zhangzhou, Fujian province April 7, 2015. (Photo by Reuters/Stringer)

A firefighter looks on as he and his colleagues try to extinguish a fire at a petrochemical plant in Zhangzhou, Fujian province April 7, 2015. (Photo by Reuters/Stringer)

A tree is covered with snow on a sunny spring day in the western Austrian village of Absam, Austria April 7, 2015. (Photo by Dominic Ebenbichler/Reuters)

A woman attaches a black ribbon for those killed in the sinking of Dalniy Vostok, to a Russian national flag in Vladivostok April 7, 2015. A Russian trawler Dalniy Vostok sank in the Sea of Okhotsk off Russia's far eastern Kamchatka peninsula on April 2, 2015, killing at least 56 of the 132 crew, the emergencies ministry said on April 2. (Photo by Yuri Maltsev/Reuters)

A chicken walks past a car decorated in the colours of the United Kingdom Independence Party (UKIP) on Sunnyhill Farm in Martson, central England, April 7, 2015. (Photo by Darren Staples/Reuters)

A zebra grazes at Nairobi National Park outside the Kenyan capital Nairobi April 6, 2015. Hoteliers from Kenya's Indian Ocean coast region and sprawling game park reserves said tourists have started cancelling trips to the east African nation after Islamist gunmen last week killed 148 people at a university campus. (Photo by Goran Tomasevic/Reuters)

Ugandan policemen hold their weapons as they ride on the back of a truck during an arrest of people suspected of murdering Joan Kagezi, a senior Ugandan prosecutor, on the outskirts of Uganda's capital Kampala April 7, 2015. Kagezi was shot dead late on March 30, in what police said could be a targeted assassination connected to her prosecution of suspects in twin bombings in the capital Kampala claimed by the Somali Islamist rebel group al Shabaab. (Photo by James Akena/Reuters)

French singer of Tunisian descent Laam arrives to attend a state dinner in honour of Tunisian President Beji Caid Essebsi at the Elysee Palace in Paris, April 7, 2015. Tunisian President Beji Caid Essebsi meets his French counterpart Francois Hollande on the state visit to France in the wake of attacks in Tunis and Paris. (Photo by Philippe Wojazer/Reuters)

A man rides a penny-farthing bicycle along Market Street in San Francisco, California April 7, 2015. (Photo by Robert Galbraith/Reuters)

A Samsung Galaxy S6 Edge smartphone motherboard is removed during a product teardown in this photo provided by iFixit in San Luis Obispo, California April 7, 2015. Samsung Electronics Co Ltd used more of its own chips to power the new Galaxy S6 smartphone than it did for the predecessor S5, according to an early teardown report, in a blow to U.S. chip supplier Qualcomm Inc. Samsung is not only using its own Exynos mobile processor, as had been widely reported, but also decided to rely on its in-house semiconductor business to source other parts, including the modem and power management integrated circuit chips, Ottawa-based consultancy Chipworks said in a web posting dated April 2. (Photo by Reuters/iFixit)

Vehicles are seen along a street in Hanoi March 30, 2015. Famous for its swarms of scooters, Vietnam is seeing auto sales surge amid the rapid expansion of a young, style-conscious middle class after 15 straight years of economic growth of over 5 percent. (Photo by Reuters/Kham)

A woman rides a motorcycle among cars along a street in Hanoi March 30, 2015. (Photo by Reuters/Kham)

Vehicles are seen along a street in Hanoi March 30, 2015. (Photo by Reuters/Kham)

Employees stand around the Indian Navy's first Scorpene submarine before being undocked from Mazagon Docks Ltd, a naval vessel ship building yard, in Mumbai April 6, 2015. Irked by India's status as the world's biggest arms importer, Prime Minister Narendra Modi wants to build an advanced defence industry but almost a year into his “Make in India” campaign, which aims to turn the country into a manufacturing powerhouse, not one large domestic weapons project has been awarded. (Photo by Shailesh Andrade/Reuters)

A girl uses her mobile phone to take pictures of a statue of Jesus at the Metropolitan Cathedral in Managua April 7, 2015. (Photo by Oswaldo Rivas/Reuters)

Disabled Palestinians participate in a race during an event organized by United Nations at a U.N-run training center in Khan Younis in the southern Gaza Strip April 8, 2015. The event was aimed at raising awareness on the impact of Explosive Remnants of War (ERW), officials said. (Photo by Ibraheem Abu Mustafa /Reuters)

Pope Francis embraces a man as he leaves at the end of his Wednesday general audience in Saint Peter's Square at the Vatican April 8, 2015. (Photo by Tony Gentile/Reuters)

Japan's Emperor Akihito (R) and Empress Michiko (front, R) receive flowers from a local girl upon their arrival at Palau international airport in Airai on Palau's Babelthuap Island, in this photo released by Kyodo April 8, 2015. Emperor Akihito arrived the island nation of Palau on Wednesday where he will visit a World War Two battlefield, the latest journey in his efforts to soothe the wounds of a conflict that haunts Asia 70 years after its end. (Photo by Reuters/Kyodo News)

Residents ride on top of an overcrowded "Jeepney", a locally manufactured public transport, along a highway in Mogpog town on Marinduque island in central Philippines April 8, 2015. (Photo by Erik De Castro/Reuters)

Republican guards stand inside the Salon des Arcades at the Hotel de Ville, city hall, in Paris, during a ceremony April 8, 2015. (Photo by Charles Platiau/Reuters)

A shoe cleaner holds a picture of National Congress Party's (NCP) presidential candidate, Sudan's President Omar Hassan al-Bashir during a campaign rally at Al Fashir in North Darfur, ahead of the 2015 elections, April 8, 2015. (Photo by Mohamed Nureldin Abdallah/Reuters)

Supporters of the National Congress Party (NCP) and presidential candidate, Sudan's President Omar Hassan al-Bashir ride camels and horses to attend the last campaign rally for the states at Al Fashir in North Darfur, ahead of the 2015 elections, April 8, 2015. (Photo by Mohamed Nureldin Abdallah/Reuters)

Supporters of the National Congress Party's (NCP) presidential candidate, Sudan's President Omar Hassan al-Bashir wave as they gather during a campaign rally at Al Fashir in North Darfur, ahead of the 2015 elections, April 8, 2015. (Photo by Mohamed Nureldin Abdallah/Reuters)

Supporters of the National Congress Party's (NCP) presidential candidate, Sudan's President Omar Hassan al-Bashir hold banners as they gather at a campaign rally at Al Fashir in North Darfur, ahead of the 2015 elections, April 8, 2015. The banner (front L) reads: “Bashir is the leader of rehabilitation”. (Photo by Mohamed Nureldin Abdallah/Reuters)

A photographer takes a picture of “Woman with shopping” by Ron Mueck during the unveiling of the Arts & Food exhibition at the Triennale as part of the upcoming Expo 2015 in downtown Milan April 8, 2015. The theme of this year's Expo is “Feeding the Planet, Energy for Life”, and it will run from May 1 to October 31, 2015. (Photo by Stefano Rellandini/Reuters)

A woman watches a creation by Tom Friedman “Big Big Mac” during the unveiling of Arts & Food exhibition at the Triennale in Milan, Italy, Wednesday, April 8, 2015. The exhibition is part of the Expo 2015 in Milan, whose theme is “Feeding the Planet, Energy for Life”. (Photo by Luca Bruno/AP Photo)

A jogger enjoys a run near the Eiffel Tower on a warm and sunny day in Paris April 8, 2015. (Photo by Gonzalo Fuentes/Reuters)

Dancers perform during the rehearsal of “Hearts and Arrows”, a creation by French dancer and choreographer Benjamin Millepied for L.A. Dance Project company at the Theatre du Chatelet in Paris April 8, 2015. The Los Angeles dance crew will perform three new works from April 8 to April 11 in Paris for the third consecutive season. (Photo by Philippe Wojazer/Reuters)

Benjamin Millepied (R), French dancer, choreographer and director of dance of the Paris National Opera (Opera National de Paris), directs dancers during the rehearsal of “Hearts and Arrows”, a creation for L.A. Dance Project company at the Theatre du Chatelet in Paris April 8, 2015. (Photo by Philippe Wojazer/Reuters)

Dancers Charlie Hodges and Stephanie Amurao perform during the rehearsal of “Hearts and Arrows”, a creation by French dancer and choreographer Benjamin Millepied for L.A. Dance Project company at the Theatre du Chatelet in Paris April 8, 2015. (Photo by Philippe Wojazer/Reuters)