In this October 21, 2015, file photo, a young man rides a hoverboard along a Manhattan street toward the Empire State Building in New York. More than 500,000 hoverboards are being recalled after reports that they can burst into flames. The Consumer Product Safety Commission said Wednesday, July 6, 2016, it has received 99 reports of battery packs in the two-wheel motorized scooters catching fire or exploding that causing burns or property damage. The recalled hoverboards were made by eight companies. (Photo by Kathy Willens/AP Photo)

Performer Zhang Yashu from a Chinese ballet company perform during a photo shoot in front of the Australia's iconic landmarks Opera House (L) and Habour Bridge in Sydney on February 17, 2014. One of China's celebrated dance campanies is bringing one of the country's biggest ballet production to Australia for a series of performances in Sydney and Melbourne. (Photo by Saeed Khan/AFP Photo)

A picture shows the blood stained floor of a kindergarten following reported shelling in the rebel-held area of Harasta, on the northeastern outskirts of the capital Damascus, on November 6, 2016. At least four children were killed and 19 people injured in the government strike in Harasta, according to the Syrian Observatory for Human Rights. (Photo by Sameer Al-Doumy/AFP Photo)

Three Palestinian women sit on a beachfront as a wave comes rushing by in Gaza City on November 17, 2016. (Photo by Mohammed Abed/AFP Photo)

Men help a woman affected by tear gas used by National Police officers to disperse a demonstration of supporters of Fanmi Lavalas political party in the streets of Port-au-Prince, Haiti, November 22, 2016. (Photo by Andres Martinez Casares/Reuters)

An airplane is silhouetted at sunrise, seen from the suburb of Saint-Cloud, near Paris, France, 08 December 2016. Paris is undergoing a third day pollution spike, prompting the city to limit vehicle circulation. (Photo by Ian Langsdon/EPA)

Damir Sagolj has won Reuters photojournalist of the year for his 2016 work, which included documenting the deadly Philippine drug war and the North Korea congress. Here: A 17 year old girl lays dead next to her doll after she and her friend were killed by unknown motorcycle-riding gunmen, in an alley in Manila, Philippines early October 26, 2016. According to the police, a sign on a cardboard reading “Tulak ka, hayop ka”, which translates to “You are a (drug) pusher, you are an animal” was found with the body of girl's friend. (Photo by Damir Sagolj/Reuters)

A girl is splashed with water by boys following a Polish Wet Easter Monday tradition, in Wilamowice, Poland, Monday, April. 17, 2017. (Photo by Jarek Praszkiewicz/AP Photo)