An OV-10 Bronco aircraft, decorated with World War One commemoration motifs, flies over Flanders international airport, ahead of the world's first Short Take Off & Landing competition on sand, in Wevelgem, Belgium May 8, 2018. (Photo by Francois Lenoir/Reuters)

Russia' s President Vladimir Putin (L) congratulates prizewinners at the 2018 Youth Judo Tournament dedicated to Soviet and Russian judo coach Anatoly Rakhlin, and held at St Petersburg' s Yubileyny Palace of Sports in St Petersburg, Russia on May 23, 2018. (Photo by Mikhail Metzel/TASS)

Emma Sees, Valor Christian, #6, accidentally grabs Windsor's Alexa Kopren's hair while both were chasing after the ball in the second half of the Colorado State girls 4A soccer championship at Dick's Sporting Goods Park May 23, 2018. (Photo by Andy Cross/The Denver Post)

A woman takes pictures as Britain driver Lewis Hamilton steers his Mercedes during the third free practice at the Monaco racetrack, in Monaco, Saturday, May 26, 2018. The Formula one race will be held on Sunday. (Photo by Luca Bruno/AP Photo)

A demonstrator is detained during May Day rallies in Santiago May 1, 2013. (Photo by Ivan Alvarado/Reuters)

Participants of the the goth festival “Wave Gothic Festival” walk in fancy costumes along the festival area in Leipzig, central Germany, Saturday, May 23, 2015. About 20,000 members of the scene are expected to attend one of the world's largest gothic and “dark” culture festivals until May 25, 2015. (Photo by Jens Meyer/AP Photo)

People walk past the Sleepwalker, a sculpture along the High Line in New York, US on May 10, 2016. The hyperrealistic work by Brooklyn artist Tony Matelli is part of the linear park’s Wanderlust exhibition. (Photo by Xinhua/Barcroft Images)

A picture made available on 13 May 2016 shows A Tiwa girl performing her traditional dance as they celebrated the Wanchuwa festival in Karbi Anglong District of Assam state, India, 11 May 2016. Wanchuwa is one of the most important festivals of the Tiwa tribal community living in the hills as it is related with agriculture which is the mainstay of their economy. Tiwas pray for a bountiful harvest during this festival and to protect their crops from pest and other natural calamities. Tiwa is a major tribe of Assam state who practice Jhum or shifting cultivation for their living in the hills. (Photo by EPA/Stringer)