Lightning illuminates a thundercloud as a storm front hits the North Sea region near Westerhever, northern Germany, on August 11, 2014. (Photo by Daniel Reinhardt/AFP Photo/DPA)
This long exposure picture shows vehicles on roads during rush hour on the eve of the National Day holidays in Shanghai on September 30, 2014. According to local media, police checkpoints will be set up at highways, elevated roads and business hubs to tackle drunk driving during the National Day holiday. (Photo by Johannes Eisele/AFP Photo)
A passenger waits after his train arrived in Nouadhibou, Mauritania’s second largest city and the main export port for the country’s iron ore industry, on June 25, 2014. The mining company’s employees proudly call their firm the lung of their nation's economy and the train that ferries the ore to the coast stretches some two kilometres, making it one of the world's longest. SNIM mines black iron ore in the northern town of Zouerate, a remote desert location which nevertheless attracts people from all over the country looking for work. (Photo by Joe Penney/Reuters)
A police officer stands at a police cordon near the scene of a terror attack in London, U.K., on Sunday, June 4, 2017. A van swerved into Saturday-night crowds on London Bridge, before three men got out and went on a stabbing rampage through nearby bars. (Photo by Luke MacGregor/Bloomberg)
Medic James E. Callahan of Pittsfield, Mass., gives mouth-to-mouth resuscitation to a dying soldier in war zone D, about 50 miles northeast of Saigon, June 17, 1967. Thirty-one men of the 1st Infantry Division were reported killed in the guerrilla ambush, with more than 100 wounded. (Photo by Henri Huet/AP Photo)
Former Olympic gymnast Nastia Liukin performs a flip while throwing the ceremonial first pitch during a baseball game between the Los Angeles Angels and the Tampa Bay Rays, Friday, July 14, 2017, in Anaheim, Calif. (Photo by Jae C. Hong/AP Photo)
Deputies in the Ukrainian parliament brawled in the chamber on Tuesday, April 8, 2014 after a communist leader accused nationalists of playing into the hands of Russia by adopting extreme tactics early in the Ukrainian crisis. Two deputies from the Svoboda far-right nationalist party took exception to the charges by communist Petro Symonenko and seized him while he was talking from the rostrum. (Photo by Valentyn Ogirenko/Reuters)