People walk past part of an outdoor display as preparations continue for the upcoming pop culture convention Comic Con in San Diego, California, U.S., July 17, 2018. (Photo by Mike Blake/Reuters)

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)

People with a South Korean flag waves as fireworks get off outside the stadium during the opening ceremony of the Pyeongchang 2018 Winter Olympic Games at the Pyeongchang Stadium on February 9, 2018. (Photo by Martin Bernetti/AFP Photo)

People look at a downhill rider during the Urban Bike Inder Medellin race final at the Comuna 1 shantytown in Medellin, Antioquia department, Colombia on November 19, 2017. (Photo by Joaquin Sarmiento/AFP Photo)

People at a Czech Stop look at a cloud of smoke rising from the explosion in West, Texas, April 17, 2013. (Photo by Andy Bartee via Dallas Morning News/MCT)

Some 300 girls and women in India still practise open defecation. Over half the country’s population, 800 million people, do not have access to a toilet that meets basic standards. (Photo by Poulomi Basu/WaterAid)

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)

Protestors affiliated with the Occupy Wall Street movement block the entrance to the Iowa Democratic Party headquarters during a protest on December 29, 2011 in Des Moines, Iowa. Thirteen people were arrested during the protest. (Photo by Andrew Burton/Getty Images)