Demonstrators wear skull masks during an anti government protest, as Chile's President Michelle Bachelet delivers a speech inside the National Congress, in Valparaiso city, Chile May 21, 2016. (Photo by Ivan Alvarado/Reuters)

A woman mourns over the coffin of a relative after a deadly eruption of Mount Sinabung in Sukandebi village, Karo, North Sumatra, Indonesia May 22, 2016, in this photo taken by Antara Foto. The volcano in western Indonesian unleashed hot clouds of ash on Saturday, killing several villagers, an official said. (Photo by Irsan Mulyadi/Reuters/Antara Foto)

U.S. Democratic presidential candidate Hillary Clinton takes a photo with supporters John Nelson, 32, (L) and Dan Stifler, 32, (C) after speaking at the UFCW Union Local 324 in Buena Park, California, U.S. May 25, 2016. (Photo by Lucy Nicholson/Reuters)

The manager of Jinhua Partytime Latex Art and Crafts Factory wears a mask of U S. Democratic presidential candidate Bernie Sanders as he poses and gives a thumbs-up as during a presentation of products to reporters at his factory's showroom in Jinhua, Zhejiang Province, China, May 25, 2016. (Photo by Aly Song/Reuters)

A woman looks out of her house with a decorated doorway during Corpus Christi day in Zahara de la Sierra, southern Spain, May 29, 2016. The village of Zahara de la Sierra celebrated the feast of Corpus Christi (or Body of Christ in Latin) by covering the streets and facades of houses with the branches of trees and grass. (Photo by Jon Nazca/Reuters)

Handguns turned in from the public as part of the “Gun Turn-in” event where a $100 gift card is given for every firearm and a $10 gift card for each BB-gun, air-gun, or replica firearm turned over to police at Universal Missionary Baptist Church in Chicago, Illinois, U.S. May 28, 2016. (Photo by Jim Young/Reuters)

An interior of a car damaged by the floods is pictured in the town of Braunsbach, Germany, May 30, 2016. The flood tore through Braunsbach, crushing cars, ripping corners of houses and flooding homes during a storm that hit southwestern Germany. Miraculously no one in Braunsbach was killed, though three people died as a result of the storm in other parts of the country. (Photo by Kai Pfaffenbach/Reuters)

A hat and boots belonging to a volunteer with the Israeli Antique Authority are seen inside the Cave of the Skulls, an excavation site in the Judean Desert near the Dead Sea, Israel June 1, 2016. A team of volunteers and archaeologists are searching for remains of The Dead Sea Scrolls, one of the oldest known Hebrew texts, in a national bid, initiated by the Israel Antiquities Authority (IAA), to prevent the robbery of such important artefacts and once found to hand them over to the state for preservation. (Photo by Ronen Zvulun/Reuters)