Dogs perform during “Stars and starlets”, a new programme, at the National Circus in the Ukrainian capital of Kiev April 30, 2015. (Photo by Gleb Garanich/Reuters)

Sumo wrestlers compete during the “Honozumo” ceremonial sumo tournament at the Yasukuni Shrine in Tokyo April 3, 2015. (Photo by Thomas Peter/Reuters)

Kashmiri vegetable vendors assemble at a floating market in the interiors of the Dal Lake in Srinagar April 17, 2012. (Photo by Danish Ismail/Reuters)

An artist draws a tattoo on a woman's arm during a tattoo convention in Ljubljana April 18, 2015. (Photo by Srdjan Zivulovic/Reuters)

A Saudi soldier fires a mortar towards Houthi movement position, at the Saudi border with Yemen April 21, 2015. (Photo by Reuters/Stringer)

Businesswoman and vendor Sonia Maria Paypay sells clothing at a stand at the commercial zone of Gamarra in Lima, April 16, 2015. (Photo by Mariana Bazo/Reuters)

A runner in fancy dress participates in the Virgin London Marathon 2013 on April 21, 2013 in London, England. (Photo by Tom Dulat/Getty Images)

A general view of the ghost town of a former Soviet military radar station near Skrunda, Latvia, April 9, 2016. (Photo by Ints Kalnins/Reuters)