A masked reveller poses near Saint Mark's Square during the Venetian Carnival in Venice January 31, 2015. (Photo by Stefano Rellandini/Reuters)

A trader weighs tobacco at a market in el-Fasher, in North Darfur February 5, 2015. Tobacco is one of the North Darfur war zone's main cash crops. (Photo by Mohamed Nureldin Abdallah/Reuters)

A Ukrainian serviceman who fought in Debaltseve is seen near Artemivsk February 19, 2015. Fighting raged in eastern Ukraine on Thursday despite European efforts to resurrect a still-born ceasefire, a day after pro-Russian separatists who spurned the truce forced thousands of government troops out of a strategic town. (Photo by Gleb Garanich/Reuters)

A participant poses backstage before a drag queen competition during carnival festivities in Las Palmas on the Spanish Canary Island of Gran Canaria February 20, 2015. (Photo by Borja Suarez/Reuters)

A participant falls on vintage skis during a traditional historical ski race in the northern Bohemian town of Smrzovka February 21, 2015. (Photo by David W. Cerny/Reuters)

Vickie Leuenberger (L) practices with a mermaid tail with AquaMermaid founder Marielle Chartier Henault in a pool in Montreal, February 19, 2015. The school teaches kids and adults how to swim wearing mermaid tails, and offers mermaid-themed parties. (Photo by Christinne Muschi/Reuters)

A church made entirely from ice is seen during the night at Balea Lac resort in the Fagaras mountains January 29, 2015. (Photo by Radu Sigheti/Reuters)

Ukrainian President Petro Poroshenko gestures during a news conference in Kiev, Ukraine, June 5, 2015. REUTERS/Mykhailo Markiv/Ukrainian Presidential Press Service/Pool