Rioters scuffle with police on a street in Mongkok district of Hong Kong, Tuesday, February 9, 2016. Rioters clashed with police overnight and into the early hours of Tuesday in a crowded area of Kowloon. The unrest started when local authorities tried to prevent street food sellers from operating on Monday night. Activists who are dissatisfied with Hong Kong's administration took part in the clashes, local media reports said. (Photo by Kin Cheung/AP Photo)

Indigenous Sahrawi girls play on an improvised see-saw at a refugee camp of Boudjdour in Tindouf, southern Algeria March 3, 2016. UN Secretary General Ban Ki-moon is scheduled to visit the Sahrawi refugees in south-west Algeria's Tindouf region. (Photo by Zohra Bensemra/Reuters)

Owner Elizabeth Wilson groomes her Chinese Crested and Coton De Tulear dogs during the annual Crufts Dog Show at the NEC Arena in Birmingham, Britain, March 10, 2016. The world's largest dog show will be held from March 10 to 13 with 22,000 dogs competing for the world class title of Crufts Best In Show. (Photo by Nigel Roddis/EPA)

A French Air Force Mirage 2000 fighter jet takes off during the close air support (CAS) exercise Serpentex 2016 hosted by France in the Mediterranean island of Corsica, at Solenzara air base, March 17, 2016. Serpentex is an annual exercise that involves joint terminal attack controllers (JTACs) from 12 countries from March 7 to March 25, 2016. (Photo by Charles Platiau/Reuters)

Cast member Ana de Armas poses during a photocall for the film “Hands of stone” out of competition at the 69th Cannes Film Festival in Cannes, France, May 16, 2016. (Photo by Regis Duvignau/Reuters)

A demonstrator kicks a riot police vehicle during an unauthorized march called by the Chilean student federations to protest against government's education reform, in Santiago, Chile July 5, 2016. (Photo by Ivan Alvarado/Reuters)

People jump over a campfire during a celebration on the traditional Ivana Kupala (Ivan the Bather) holiday, the ancient tradition, originating from pagan times, is usually marked with grand overnight festivities during which people sing and dance around campfires, believing it will purge them of their sins and make them healthier, in Kiev, Ukraine, July 6, 2016. (Photo by Gleb Garanich/Reuters)

Workers clean empty cooking oil containers at a roadside recycling workshop in Kolkata, India, July 13, 2016. (Photo by Rupak De Chowdhuri/Reuters)