A view of the scene of a train accident after two commuter trains collided head-on near the town of Andria, in the southern region of Puglia, killing several people, Tuesday, July 12, 2016. (Photo by Luca Turi/ANSA via AP Photo)

Turkana tribesmen walk with guns in order to protect their cattle from rival Pokot and Sambur tribesmen near Baragoy, Kenya February 14, 2017. Cattle rustling and competition for grazing have long troubled northern Kenya, but severe drought and political rivalries ahead of the elections have exacerbated the situation between ethnic tribes. (Photo by Goran Tomasevic/Reuters)

A protestor gestures toward the White House on the Ellipse near the South Lawn of the White House during the Women's March on Washington January 21, 2017 in Washington, DC. Large crowds are attending the anti-Trump rally a day after U.S. President Donald Trump was sworn in as the 45th U.S. president. (Photo by Drew Angerer/Getty Images)

Police officers clear the area near Borough market at London Bridge on June 3, 2017 in London, England. Police have responded to reports of a van hitting pedestrians on London Bridge in central London. (Photo by Dan Kitwood/Getty Images)

An officer of the Afghan border police throws an assault rifle to a policeman participating in a military exercise on the outskirts of Herat, Afghanistan, Monday, September 7, 2015. Twelve female and seventy male border police personnel participated in the military exercise near the border with Iran in Herat province. (Photo by Hoshang Hashimi/AP Photo)

A 1964 Amphicar driven by James Spear of Henderson, Nevada is shown on the boat launch after a trip to Hoover Dam during the first Las Vegas Amphicar Swim-in at Lake Mead near Las Vegas, Nevada October 9, 2015. The German-made Amphicar was produced from 1961-1968. (Photo by Steve Marcus/Reuters)

Police react to a suspicious vehicle near La Carillon restaurant following a series of deadly attacks in Paris, November 15, 2015. Thousands of French troops deployed around Paris on Sunday and tourist sites stood shuttered in one of the most visited cities on Earth while investigators questioned the relatives of a suspected suicide bomber involved in the country's deadliest violence since World War II. (Photo by Pascal Rossignol/Reuters)

A man carries an injured child amidst rubble near a burning vehicle in a site damaged from what activists said was shelling by forces loyal to Syria's President Bashar al-Assad in the town of Douma, eastern Ghouta in Damascus, Syria December 30, 2015. (Photo by Bassam Khabieh/Reuters)