In a July 14, 1967 file photo, left, National Guardsmen make their way along Market Street in Newark, N.J, after an evening of deadly rioting and looting in what came to be known as the Newark riots. In a June 16, 2017 photo, right, an ambulance drives on the same block 50 years later. (Photo by AP Photo/File, left; Julio Cortez, right)

View at one of the sculptures by Swiss artist H.R. Giger during the opening of the Ars Electronica 2013 exhibition “HR Giger. The Art of Biomechanics” in Linz, Austria, 04 September 2013. (Photo by EPA/RUBRA)

Children of Indian laborers play on make-shift swings in Amritsar, India, May 12, 2015. (Photo by Narinder Nanu/AFP Photo)

Young Christian Lebanese women, who are members of Kataeb Phalangist party, show their skill in handling arms while they train in a village between Christian-controlled eastern port of Jounieh and the Christian village of Zahle in the west Lebanon on September 9, 1976. The Lebanese civil war erupted in April 1975. (Photo by Erich Stering/AFP Photo)

An elephant mahout (trainer) lies on his elephant his feet resting on its ears as it rests and eats prior to opening day's play at the King's Cup Elephant Polo Tournament 2014 held near Bangkok, in Samut Prakan province, Thailand, 28 August 2014. The annual charity tournament runs until 31 August and involves 51 elephants who normally live on the streets and are used for begging. Sixteen competing elephant polo teams from 40 different nations take part in the charity event directed at raising funds to improve the lives of the elephants and elephant conservation in general. (Photo by Barbara Walton/EPA)

People wearing costumes attend the annual water-splashing festival to mark the New Year of the Dai minority in Jinghong, Yunnan province, April 13, 2015. (Photo by Reuters/China Daily)

Classic antique cars are seen at an auto dealer in West Branch, Iowa, March 6, 2015. Iowa, the American heartland. Endless farm fields and quiet towns. 56,273 square miles that are soon to become the focus of the nation as the long process of electing the next U.S. president begins. (Photo by Jim Young/Reuters)

A girl cover her face while riding a motorcycle as haze shrouds a street near Tanjung Siapi Api port in Palembang, on the Indonesian island of Sumatra, September 19, 2015. Indonesia will take 30 days to bring smouldering forest fires under control, the national disaster management agency said on Friday, as smog from the fires pushes pollution in Southeast Asia to record highs. (Photo by Reuters/Beawiharta)