A Christian worshipper reacts as she takes part in the Christian Orthodox Holy Fire ceremony at the Church of the Holy Sepulchre in Jerusalem's Old City, April 30, 2016. (Photo by Amir Cohen/Reuters)

Riot police runs as a woman falls down during a May Day rally in the Kreuzberg district of Berlin, Germany, 01 May 2016. (Photo by Kay Nietfeld/EPA)

Ukrainians pour water on each other on a street in Lviv, Ukraine, 02 May 2016. The tradition of pouring water was an ancient spring ritual of cleansing on first Monday after Orthodox Easter. (Photo by Mykola Tys/EPA)

Boys play with water as they celebrate Myanmar's New Year Water Festival of Thingyan in Yangon, April 13, 2016. (Photo by Soe Zeya Tun/Reuters)

Villagers take part in a ritual celebrating the pagan god Yurya and pray for plentiful future harvests in the village of Pogost, Belarus May 6, 2016. (Photo by Vasily Fedosenko/Reuters)

Buddhists carry a dragon-shaped lantern during a lotus lantern parade in celebration of the upcoming birthday of Buddha in Seoul, South Korea, May 7, 2016. (Photo by Kim Hong-Ji/Reuters)

A polar bear plays with a pylon during celebrations marking its first birthday in an enclosure at Tierpark Hellabrunn zoo in Munich December 9, 2014. (Photo by Michaela Rehle/Reuters)

Gabriella Papadakis and Guillaume Cizeron of France perform during the ice dance skating event at the ISU Grand Prix of Figure Skating final in Barcelona December 13, 2014. (Photo by Albert Gea/Reuters)