Members of the New People's Army (NPA) female guerrillas perform a cultural show during the release of a Philippines army soldier in Sugbongcogon town, Misamis Oriental, southern Philippines, November 20, 2015. NPA spokesperson Allan Juanito warned that they will seize more soldiers to exchange them with the government as "Prisoners of war". (Photo by Froilan Gallardo/Reuters)

Members of the Royal Navy respond to a simulated fire in a Vanguard-class submarine control room training facility at Clyde naval base in Faslane, Scotland on January 21, 2016. (Photo by Photograph: Danny Lawson/PA Wire)

Revellers celebrate "Ash Monday" by participating in a colourful "flour war", a traditional festivity marking the end of the carnival season and the start of the 40-day Lent period until the Orthodox Easter,in the port town of Galaxidi, some 215 km (134 miles) north west of Athens, March 18, 2013. The revellers "fight" by throwing coloured flour, charcoal dust and powder painting until they essentially run out of supplies. (Photo by Yannis Behrakis/Reuters)

A “scissors” dancer grabs her shoe with her mouth while performing in a national scissors dance competition in the outskirts of Lima December 1, 2013. The Danza de las tijeras, or scissors dance, is a traditional dance from the Peruvian southern region of the Andes, in which two or more performers take turns dancing while accompanied with music from a harp and a violin. Dancers would display various skills and moves, which include cutting the air with the use of a scissors. (Photo by Enrique Castro-Mendivil/Reuters)

A performer wearing costumes walk on stilts before a show during a lantern fair at the beginning of Chinese Lunar New Year, in Xi'an, Shaanxi province, February 11, 2016. (Photo by Reuters/Stringer)

Men cover their heads from the sun while riding on a motorcycle during a hot day in Cairo, Egypt, August 17, 2015. A heatwave killed at least 61 people across Egypt from Sunday to Tuesday and caused nearly 600 people to be admitted to hospital, Egypt's health ministry said on state news agency MENA on Wednesday. (Photo by Amr Abdallah Dalsh/Reuters)

A spectator at the Maslenitsa car battle, reacts during a clash, in the village of Goroshki, some 35 kilometers from Minsk, Belarus, 12 March 2016. The battle which is held at the Historical and Cultural Complex, Stalin line, is a small local competition, with participants from Belarus and Russia. (Photo by Tatyana Zenkovich/EPA)

A photo made available on 14 March 2016 shows a Thai villager takes selfie photograph on drought parched land at the dried up Mae Chang reservoir in Lampang province, northern Thailand, 12 March 2016. The ruined village including ancient temple had been underwater for 34 years since the Mae Chang reservoir was built in 1982, the area has now re-emerged after water in the reservoir dried up caused by the severe drought. Thailand is facing the worst drought in decades hardest hit by El Nino phenomenon combined with seasonal hot weather. (Photo by Rungroj Yongrit/EPA)