Italy's new President Sergio Mattarella and Prime Minister Matteo Renzi arrive by car for a welcoming ceremony, at the Quirinale presidential palace in Rome, February 3, 2015. (Photo by Tony Gentile/Reuters)

An artificially triggered avalanche thunders down a mountain side at the Vallee de la Sionne in Anzere near Sion, February 3, 2015. The full-scale avalanche dynamics test site is providing scientists and engineers of the Swiss Institute of Research of Snow and Avalanches with essential data to understand and model avalanche motion, according to the Institute website. (Photo by Denis Balibouse/Reuters)

An artificially triggered avalanche thunders down a mountain side at the Vallee de la Sionne in Anzere near Sion, February 3, 2015. (Photo by Denis Balibouse/Reuters)

An artificially triggered avalanche thunders down a mountain side at the Vallee de la Sionne in Anzere near Sion, February 3, 2015. (Photo by Denis Balibouse/Reuters)

Cuneiform tablets are displayed during an exhibition at the Bible Lands Museum in Jerusalem, February 3, 2015. The exhibition of ancient clay tablets from modern-day Iraq is shedding light for the first time on the daily lives of Jews who were exiled to Babylon from Jerusalem some 2,500 years ago. The exhibition is based on more than 100 cuneiform tablets, each no bigger than an adult's palm, that detail transactions and contracts between Judeans driven out of or convinced to move from Jerusalem by King Nebuchadnezzar in 600 BC. (Photo by Baz Ratner/Reuters)

The new KC-390 military cargo jet, is pictured in Gaviao Peixoto city near Sao Paulo February 3, 2015. Embraer's new military cargo jet flew for the first time on Tuesday and the planemaker is making progress on collecting late government payments in the next few months, the company's defense chief said in an interview. Brazil's defense ministry has invested heavily in the KC-390 program, covering $2 billion in development costs and signing a 7.2 billion reais ($2.7 billion) order for 28 planes last year. But a tight federal budget led the defense ministry to push payment on some projects from late last year into 2015, leading Embraer to warn of negative 2014 cash flow. (Photo by Reuters/EMBRAER)

Human skulls are seen in a mass grave on the outskirts of the town of Sinjar, Iraq February 3, 2015. Police said the mass grave contained remains from 25 people belonging to the minority Yazidi sect, apparent victims of killings by Islamic State militants. (Photo by Ari Jalal/Reuters)

People look at a picture of slain Salvadoran Archbishop Oscar Romero at the national cathedral in San Salvador February 3, 2015. Pope Francis on Tuesday ruled that Romero, who was murdered by a right-wing death squad in 1980 and is an icon of the Roman Catholic Church in Latin America, had died as a martyr and will be beatified, the Vatican said. (Photo by Jose Cabezas/Reuters)

A man holds a blanket as he walks past graffiti by Brazilian artist Cranio depicting an indigenous man swimming in petroleum, on a mural highlighting the issue of severe water shortages in Sao Paulo, February 3, 2015. Residents of Brazil's largest city, Sao Paulo, could soon only have running water two days a week. The state-owned water management company last week said if rain does not replenish the depleted Cantareira reservoir system soon, they might have to start a “drastic” rationing project on a rotational basis of two days on, five days off. (Photo by Nacho Doce/Reuters)

A Metro-North Railroad passenger train smolders after hitting a vehicle in Valhalla, N.Y., Tuesday, February 3, 2015. (Photo by Frank Becerra Jr./AP Photo/The Journal News)

A car sits crushed into the front of a Metropolitan Transportation Authority (MTA) Metro North Railroad commuter train near the town of Valhalla, New York, February 3, 2015. At least six people died and 12 more were injured on Tuesday evening when the New York commuter train struck at least one car near the town of White Plains, sparking a fire, ABC News reported. (Photo by Mike Segar/Reuters)

The burned out shell of an SUV, rests against a charred Metro-North Railroad commuter train as personnel from various agencies work the scene of a deadly accident in Valhalla, N.Y., Wednesday, February 4, 2015. The packed train slammed into a SUV stuck on the tracks and erupted into flames Tuesday night, killing some and injuring others, sending hundreds of passengers scrambling for safety, authorities said. (Photo by Frank Becerra Jr./AP Photo/The Journal News)

A boy reacts after getting an autograph from former Portugal forward Luis Figo (back R) during a Figo Football Academy training session in the southern Chinese city of Guangzhou February 4, 2015. FIFA have confirmed that incumbent Sepp Blatter, Figo, Dutch FA president Michael van Praag and Prince Ali Bin Al-Hussein of Jordan have bid to stand for president. (Photo by Bobby Yip/Reuters)

Ukraine's former Prime Minister Mykola Azarov walks past a portrait of Russia's President Vladimir Putin as he attends a news conference to present his new book in Moscow February 4, 2015. Interpol has put ousted Ukrainian president Viktor Yanukovich and two members of his former government on the international wanted list at the behest of Ukraine, according to a notice on its website on January 12. Azarov was also listed though it was not clear what the Ukrainian charges against him were. (Photo by Sergei Karpukhin/Reuters)

Event employee Charlotte Martin positions place sticks for guests during preparations for British Academy of Film and Television Awards (BAFTA) ceremony at the Royal Opera House in central London, February 4, 2015. The 2015 BAFTA Awards Ceremony takes place in London on February 8. (Photo by Toby Melville/Reuters)

A gardener trims the grass at the Temple of Olympian Zeus in Athens February 4 2015. Greek yields rose on Wednesday as a media report that the ECB was unwilling to approve Athens' proposal to raise the ceiling for its treasury bill issuance cooled optimism that a compromise debt deal may be reached. (Photo by Kostas Tsironis/Reuters)

Activists protest against the Transatlantic Trade and Investment Partnership (TTIP) outside the European Commission headquarters in Brussels February 4, 2015. (Photo by Yves Herman/Reuters)

Ivan Timofeenko, co-founder of the “Newton Park” interactive museum of science, demonstrates the so-called Mirror Box, which produces various combinations of reflections creating volumetric geometric figures, during preparations for a performance for school children dedicated to the Russian Day of Science at the Museum Centre in Krasnoyarsk, Siberia, February 4, 2015. A group of young engineers, scientists and researchers, who specialize in chemistry, applied mathematics and physics, founded an interactive museum of science to conduct experiments aimed at the popularization of the exact sciences for pupils and their parents. (Photo by Ilya Naymushin/Reuters)

Participants work on a customised computer at Campus Party event in Sao Paulo February 4, 2015. Campus Party is an annual week-long, 24-hour technology festival that gathers around 8,000 hackers, developers, gamers and computer enthusiasts from around the world. (Photo by Paulo Whitaker/Reuters)

Sellers sit at a stand selling bananas at a wholesale fruit market in Lima, Peru February 4, 2015. (Photo by Mariana Bazo/Reuters)

A seller sits at a stand selling bananas at a wholesale fruit market in Lima, February 4, 2015. (Photo by Mariana Bazo/Reuters)

A model stands next to Samsung Electronic's S'UHD smart television sets during its launch event in Seoul February 5, 2015. (Photo by Kim Hong-Ji/Reuters)

A vendor prepares Muslim head scarves at a stall in Tanah Abang market in Jakarta February 5, 2015. Indonesia's economy in 2014 grew at its slowest pace in five years, as expected, the statistics bureau said on Thursday. Gross domestic product (GDP) expanded 5.02 percent in 2014 compared with 5.58 percent in 2013, using the statistics office's new 2010 base year. (Photo by Darren Whiteside/Reuters)

Herdsmen from the Kyrgyz ethnic group hold their falcons as they ride on horses during a hunting competition in Akqi county, Xinjiang Uighur Autonomous February 1, 2015. (Photo by Reuters/Stringer)

Chinese Kazakh eagle hunters sit on horseback as they travel to a local competition on January 29, 2015 in the mountains of Qinghe County, Xinjiang, northwestern China. The festival, organised by the local hunting community, is part of an effort to promote and grow traditional hunting practices for new generations in the mountainous region of western China that borders Kazakhstan, Russia and Mongolia. The training and handling of the large birds of prey follows a strict set of ancient rules that Kazakh eagle hunters are preserving for future generations. (Photo by Kevin Frayer/Getty Images)

A bartender watches as an Infinium-Serve Flying Robot takes off with an order at a restaurant during a pilot demonstration for the media in Singapore February 5, 2015. The Unmanned Aerial Vehicle (UAV), a working model designed by firm Infinium Robotics that specializes in UAV solutions, aims to free up restaurant staff to do “higher value tasks” by accurately delivering orders up to 500 grams to tables within the premise by means of anti-collision algorithms, according to Chief Executive Officer Woon Junyang. The programme is currently undergoing testing for its launch at the end of the year. (Photo by Edgar Su/Reuters)

A worker pushes a cart with cans of soda past an advertisement of a Spanish shoe brand in Madrid February 5, 2015. Spain's service sector grew at its fastest rate in five months, a poll showed on Wednesday, and firms hired staff faster as the country consolidated its return to economic expansion. (Photo by Susana Vera/Reuters)

Visitors interact with the “Jump In” installation at the Pearlfisher gallery in west London February 5, 2015. (Photo by Neil Hall/Reuters)

A visitor interacts with the “Jump In” installation at the Pearlfisher gallery in west London February 5, 2015. (Photo by Neil Hall/Reuters)

A woman and child walk past a residential building decorated with graffiti reading “Yura, we have improved!” and depicting Soviet cosmonaut Yuri Gagarin, a map of Crimea, a Sukhoi Superjet 100, a 2014 Sochi Olympic medal, a Russian rouble sign and an oil platform, in Moscow, February 5, 2015. (Photo by Maxim Zmeyev/Reuters)

A camera drone operated by a civilian flies near the scene where two buildings were destroyed in an explosion in New York, in this file photo taken March 12, 2014. Some 73 percent of respondents to a Reuters/Ipsos online poll released on Thursday said they want regulations for the lightweight, remote-control planes that reportedly have been involved in an increasing number of close calls with aircraft and crowds. (Photo by Mike Segar/Reuters)

Three of Jupiter's largest moons are seen moving across the banded face of Jupiter in these images from NASA's Hubble Space Telescope taken January 24, 2015 and released February 5, 2015. Jupiter's four largest moons can commonly be seen transiting the face of the giant planet and casting shadows onto its cloud tops. However, seeing three moons transiting the face of Jupiter at the same time is rare, occurring only once or twice a decade, according to a NASA news release. (Photo by Reuters/NASA)

A riot police armoured personnel carrier is seen engulfed with fire from a molotov cocktail thrown by protesters during clashes in the village of Bilad Al Qadeem south of Manama, February 5, 2015. Protesters clashed with riot police demanding for the release of Bahraini opposition leader Sheik Ali Salman. Sheik Salman, head of the al-Wefaq Islamic Society was arrested on December 28, 2014 after leading a protest rally against elections in November which his party boycotted. (Photo by Hamad I. Mohammed/Reuters)

Runners brave the blowing snow during the Super Bowl Shuffle 5K in Geneva, Ill., Sunday, February 1, 2015. A slow-moving winter storm blanketed a large swath of the Plains and Midwest in snow Sunday, forcing the cancellation of more than 1,500 flights and making roads treacherous. (Photo by Mark Black/AP Photo/Daily Herald)