Passengers prepare to take part in the No Pants Subway Ride in Prague, Czech Republic, Sunday, January 8, 2017. The No Pants Subway Ride began in 2002 in New York as a stunt and has taken place in cities around the world since then. (Photo by Petr David Josek/AP Photo)

This picture taken on March 21, 2015 shows a couple kissing in front of blooming cherry blossoms in Wuhan in central China's Hubei province. The cherry blossoms, now in full bloom, attracted tens of thousands of visitors, local media reported. (Photo by AFP Photo/Stringer)

In this photo taken Tuesday, April 14, 2015, immigrant men armed with machetes make their way onto a Durban, South Africa, street during clashes with police and in search of locals that attacked foreign shop owners in the city center. (Photo by Tebogo Letsie/AP Photo)

People attend a Halloween event at Ocean Park on October 30, 2015 in Hong Kong. Halloween – a named taken from 'All Hallows' Even' falls on the day before All Saints' Day on November 1 – a holiday when Christians remember their deceased loved ones. (Photo by Anthony Kwan/Getty Images)

In this photo taken late Thursday, May 7, 2015, a prison guard, left, and seated inmates cast shadows on a wall while waiting for the beginning of a rock concert by Romanian band Pro Musica, inside the Popa Sapca jail in Timisoara, western Romania. (Photo by Adi Piclisan/AP Photo)

In this photo taken on Saturday, November 16, 2013, Mt. Etna, Europe's most active volcano, spews lava during an eruption as seen from Acireale, near the Sicilian town of Catania, Italy. (Photo by Carmelo Imbesi/AP Photo)

This picture taken on July 9, 2013 shows heavy flood waters sweeping through Beichuan in southwest China´s Sichuan province. Rainstorms sweeping across parts of China have affected millions, causing landslides and disabling transportation in provinces such as Sichuan and Yunnan, state media reported. (Photo by AFP Photo)

Chinese hostesses, who serve the delegates of the Chinese People's Political Consultative Conference and National People's Congress, have souvenir photos taken in front of the Great Hall of the People during sessions of the CPPCC and NPC held in Beijing, China Tuesday, March 4, 2014. (Photo by Andy Wong/AP Photo)