A prisoner from the Pedrinhas prison is carried to receive medical help after he was injured during a fight between rival gangs inside the jail, in Sao Luiz, capital of Maranhao state, January 8, 2014. The recent posting on a major Brazilian news website of a video filmed last December 17 by Pedrinhas prisoners of the decapitated and tortured bodies of rival inmates inside the jail has highlighted some of the problems present in the country's prison system which houses nearly twice as many prisoners as its capacity, according to official statistics. (Photo by Douglas Cunha/Reuters/O Estado do Maranhão)

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)

Attnedees dressed in Zombie outfits walk down the Gaslamp Quarter outside of the 2015 Comic-Con International in San Diego, California July 8, 2015. (Photo by Sandy Huffaker/Reuters)

A kid from Sichuan provice smokes at an assistance center February 23, 2005 in Shenzhen, Guangdong Province, China. The kids, ranging in age from 7 to 16, are temporary residents of the center, one of the institutions established by China's departments of civil affairs to help and administer beggars, vagrants and juvenile delinquents, after rescission of China's compulsory detainment and relocation system. (Photo by Cancan Chu/Getty Images)

A huge wave crashes against Castlerock pier as professional surfer Al Mennie waits on a break in the swell on December 22, 2016 in Coleraine, Northern Ireland. Storm Barbara is expected to cause major travel disruption when it hits northern parts of the UK later with 90mph winds predicted. The Met Office has issued an amber warning with the worst effects of the storm expected on Friday and Saturday. (Photo by Charles McQuillan/Getty Images)

Children play on top of an old plane's fuselage at a dump site in Paranaque city, Metro Manila, Philippines January 21, 2017. (Photo by Ezra Acayan/Reuters)

Japanese sumo wrestler Kisenosato (C) holds a red sea bream next to his stablemaster Tagonoura's wife Kotomi as he celebtares after receiving messengers from the Japan Sumo Association bringing official notice of his promotion to Yokozuna, or grand champion, during a ceremony in Tokyo, Japan, January 25, 2017. (Photo by Toru Hanai/Reuters)