This picture taken on February 23, 2014 shows participants wearing dresses running half-naked in the annual 3.5 km Undie Run held in the Olympic Forest Park smog-covered Beijing. Some 200 participants took part in this event, many of them with gas masks, as dangerous smog blighted swathes of northern China in recent days. (Photo by AFP Photo/STR)

A man poses standing on a rock looking at the aurora borealis, or northern lights, illuminating the night sky at Embleton Bay in Northumberland, England, on February 27, 2014. The northern lights is a fantastical natural light display with fast moving light effects caused by particles charged by the sun colliding with particles in Earth's upper atmosphere. (Photo by Tom White/PA Wire)

A Brazilian drug gang member nicknamed Pilintra, 26, poses with a gun atop a hill overlooking a slum in Salvador, Bahia State, April 11, 2013. One of Brazil's main tourist destinations and a 2014 World Cup host city, Salvador suffers from an unprecedented wave of violence with an increase of over 250% in the murder rate, according to the Brazilian Center for Latin American Studies (CEBELA). (Photo by Lunae Parracho/Reuters)

In this handout photo provided by Warner Brothers Pictures and Village Roadshow Pictures, Tom Cruise plays Lieutenant Colonel Bill Cage, a soldier who replays his last day while trying to fight aliens, in director Doug Liman's “All You Need Is Kill”. The film is set to premiere on March 14, 2014. (Photo by David James/Warner Brothers Pictures)

Sinabung mountain spews volcanic smoke in Tiga Pancur Village, Karo, North Sumatra, Indonesia, 09 June 2019. According to BNPB, Mount Sinabung erupted, blowing volcanic ash more than 7,000 meters high. Sinabung is one of the most active volcanos in Indonesia. It erupted in 2010 and since then killed 17 people in eruptions in 2014 and another nine people in 2016. (Photo by Sarianto Sembiring/EPA/EFE)

Abbas Alizada, who calls himself the Afghan Bruce Lee, poses during a media event in Kabul December 9, 2014. From the ruins of an iconic bombed-out palace above Kabul, the young Afghan man bearing a striking resemblance to kung fu legend Bruce Lee is high-kicking his way to Internet fame, aiming to show another side to his war-weary nation. (Photo by Mohammad Ismail/Reuters)

Pro-Russian separatists from the Chechen “Death” battalion take part in a training exercise in the territory controlled by the self-proclaimed Donetsk People's Republic, eastern Ukraine, December 8, 2014. Chanting “Allahu Akbar” (God is greatest), dozens of armed men in camouflage uniforms from Russia's republic of Chechnya train in snow in a camp in the rebel-held east Ukraine. They say their “Death” unit fighting Ukrainian forces has 300 people, mostly former state security troops in the mainly-Muslim region where Moscow waged two wars against Islamic insurgents and which is now run by a Kremlin-backed strongman. (Photo by Maxim Shemetov/Reuters)

A man holds a girl as she tries to escape when she realised she is to to be married, about 80 km (50 miles) from the town of Marigat in Baringo County, Kenya, December 7, 2014. As Pokot tradition dictates, the future husband arrived to her family home with a group of men to collect the girl. The men arrived with the last settled dowry of livestock for the girl's family. In this case it was 20 goats, three camels and 10 cows, given during a period of several weeks. (Photo by Siegfried Modola/Reuters)