Blankets cover the bodies of a woman (right) and a man (left background) hit by a northbound Penn Central train (background) as they waited with a crowd at Pennsylvania Railroad station in Elizabeth, N.J. on June 8, 1968 to view the southbound train carrying the body of Sen. Robert F. Kennedy to Washington. The woman was identified as Mrs. Antoinette Severini, 54, and the man, John Curia (age unavailable), both of Elizabeth. (Photo by AP Photo)

A demonstrator catches fire during clashes with riot police within a protest against Venezuelan President Nicolas Maduro, in Caracas on May 3, 2017. Venezuela's angry opposition rallied Wednesday vowing huge street protests against President Nicolas Maduro's plan to rewrite the constitution and accusing him of dodging elections to cling to power despite deadly unrest. (Photo by Ronaldo Schemidt/AFP Photo)

A Colombia fan clearly regrets invading the pitch as she is chased by a large security guard during the International Friendly match between Australia and Colombia at Craven Cottage on March 27, 2018 in London, England. (Photo by Charlotte Wilson/Offside/Getty Images)

A performer dances at a housing exhibition in Wuhan, Hubei province, China, September 27, 2015. (Photo by Reuters/Stringer)

Veteran racehorse Morestead models the world's first authentic Harris Tweed suit designed for a racing horse, which has been specially commissioned by William Hill to celebrate the opening of this year's Cheltenham Festival on March 15, 2016 in the U.K. (Photo by Joe Pepler/Rex Features/Shutterstock)

Singer Ariana Grande (C) performs “Side by Side” during the 2016 American Music Awards in Los Angeles, California, U.S., November 20, 2016. (Photo by Mario Anzuoni/Reuters)

In a photo taken on November 27, 2016 a female traffic police officer directs traffic on a road in Pyongyang. Believed to be hand-picked for their looks, Pyongyang's female traffic police are a familiar sight at intersections around the capital, where traffic volumes have noticeably increased in recent years. (Photo by Ed Jones/AFP Photo)

An injured man is carried atop an Iraqi special forces armored vehicle during fighting against Islamic State militants in western Mosul, Iraq, Tuesday, March 14, 2017. (Photo by Felipe Dana/AP Photo)