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)

Carlos Melendez prepares to feed his pet squirrel “Colita” in downtown San Salvador January 29, 2015. (Photo by Jose Cabezas/Reuters)

The top layer of muskeg and earth (L) is removed at the Syncrude tar sands operations near Fort McMurray, Alberta, September 17, 2014. Syncrude currently produces 350,000 barrels per day of high quality light, low sulphur crude oil according to company reports. (Photo by Todd Korol/Reuters)

A new monorail service in Houston, Texas, ready for its inaugural service. (Photo by Evans/Three Lions/Getty Images). Circa 1950

A woman walks with a squirrel on her shoulder at Maeklong market at the outskirts of Bangkok, Thailand September 20, 2016. (Photo by Jorge Silva/Reuters)

A man takes photo of his colleague with a mobile phone on the burning oil tanker at the ship-breaking yard in Gaddani, Pakistan, November 2, 2016. Reports state that at least eighteen workers were killed and more than 100 were wounded in a blast at Gaddani ship breaking yard near Karachi on 01 November. Initial reports suggest the blast occurred when a gas cylinder exploded inside an oil tanker being broken up for scrap. (Photo by Akhtar Soomro/Reuters)

People row their canoes on a flooded street at a village in Kawlin township, Sagaing division, Myanmar, July 21, 2015. Heavy rains caused flooding over 20,000 acres of rice field and in about a hundred villages, killing at least eight people, according to local media. (Photo by Soe Zeya Tun/Reuters)

Attendees at Wizard World Comic Con walk through hallways in Chicago, Illinois, United States, August 22, 2015. (Photo by Jim Young/Reuters)