A demonstrator throw a firebomb during clashes with Turkish riot police officers in Istanbul, Turkey, Friday, May 1, 2015. The government assigned 30,000 police officers backed by helicopters as workers and demonstrators determined to defy a government ban, tried to march to iconic Taksim Square, where 35 people were killed during May Day celebration in 1977. (Photo by Emrah Gurel/AP Photo)

A drone operated by paramilitary police flies over the site of last week's explosions at Binhai new district in Tianjin, China, August 17, 2015. Many operations have resumed at China's Tianjin port, trade sources said, after explosions last week that killed more than 100 people and disrupted business at what is an important oil, gas and bulk import harbor for Asia's biggest economy. The explosions on August 12 led to the disruption of all chemical and oil tanker discharges at the port, and imports of iron ore were also affected. (Photo by Kim Kyung-Hoon/Reuters)

Women pose for a picture at the entrance of the Carlton Hotel, in the government controlled area of Aleppo, Syria December 17, 2016. (Photo by Omar Sanadiki/Reuters)

Boys walk near a damaged building in the rebel held besieged city of Douma, in the eastern Damascus suburb of Ghouta, Syria December 30, 2016. (Photo by Bassam Khabieh/Reuters)

Baker Magadma, a member of Palestinian sports group Bar Palestine, performs on the street in Gaza City, on June 3, 2016. Street workout, which is still new in Gaza, is a growing sport across the world with annual competitions and events. (Photo by Mohammed Abed/AFP Photo)

A man lying on the ground is assisted by French policemen during clashes bewteen English and Russian supporters in the Old Port of Marseille, France, Saturday, June 12, 2016, before the UEFA EURO 2016 group B match between England and Russia. (Photo by Daniel Dal Zennaro/ANSA via AP Photo)

Tina Hitscherich surprises a police officer with a kiss during the NYC Pride Parade in New York, Sunday, June 26, 2016. With a moment of silence followed by the roar of motorcycles, New York City's gay pride parade kicked off Sunday, a celebration of barriers breached and a remembrance of the lives lost in the massacre at the gay nightclub in Orlando. (Photo by Seth Wenig/AP Photo)

Nigel Lamb from Great Britain, left, leading Juan Velarde of Spain, centre, and Martin Šonka of Czech Republic in the FAI Red Bull air race, Isle of Wight, UK on August 9, 2016. (Photo by Joerg Mitter/Red Bull/Global New/PA Wire)