A woman stumbes as people run down Oxford Street, London, Britain, November 24, 2017. Police are responding to reports of an incident at London's Oxford Circus Tube station and have urged the public to avoid the area. (Photo by Peter Nicholls/Reuters)

A man fires his pistol in the air during a celebratory rally after the United Nations approved a no fly zone over the country on March 18, 2011 in Tobruk, Libya. Libya declared an immediate cease-fire after the UN vote but reports indicate that Muammar Gaddafi's forces were still shelling two cities. (Photo by Joe Raedle/Getty Images)

Relatives of an earthquake victim are led away from ruins by a Policeman, on October 25, 2011 in Van, Turkey. Media are reporting more than 400 people have been killed in the 7.2 earthquake that struck in Eastern Turkey on October 23. The earthquake has left up to 40,000 people homeless in almost freezing conditions. (Photo by Ahmad Halabisaz/Getty Images)

The Brooklyn Bridge is seen after a crane pulled by a tug boat on the East River slammed into scaffolding beneath the Bridge on March 13, 2012 in New York, NY. According to reports, no damage was done to the structure of the bridge. (Photo by Allison Joyce/Getty Images)

A Manipuri woman sells smoked and dry fish in Ima market - the world's largest all women market – in Imphal city, Manipur state, 06 January 2016. The 150-year-old Ima Keithel or “Mothers's market” complex, which is run exclusively by women and was damaged in the 04 January 2016 earthquake, is returning back to normal. Nine deaths have been reported from in and around Imphal due to falling debris. Imphal has a population of some 270,000 and people were jolted from their sleep and ran out of their homes in panic when the earth shook 04 January, reports say. (Photo by EPA/Stringer)

A prototype battery-powered plane, called Greased Lightning or GL-10 is pictured flying at NASA's Langley Research Center in this undated handout photo obtained by Reuters May 1, 2015. The plane, which has 10 engines and can take off like a helicopter and fly efficiently like an aircraft, is currently in the design and testing phase. (Photo by Reuters/NASA)

Local villagers ride a local coal powered steam train on March 27, 2015 at a station in the town of Shixi , Sichuan Province, in Southern China. While China boasts the world's most extensive high-speed rail infrastructure with over 16,000 kilometers of track, the Shixi-Bagou railway is still a primary connection for local villagers between towns and is kept alive by tourist cars carrying passengers for ten times the price. The rail line came into service in the late 1950s and the train was initially used to transport coal from a now-shuttered mine before passenger carriages were added. (Photo by Kevin Frayer/Getty Images)

A woman wearing a mask reacts at her garden which locates next to chimneys of coal-fired power plant in Shijiazhuang, Hebei province, China, January 28, 2015. Beijing introduced tougher regulations this year to combat pollution, keen to overhaul China's unwanted image of smog-choked cities, fouled waterways and heavy-metal tainted soil. (Photo by Kim Kyung-Hoon/Reuters)