A woman is assisted while crossing a flooded street after the Huayco river overflooded its banks sending torrents of mud and water rushing through the streets, in Huachipa, Peru on March 17, 2017. Muddy water spilled onto streets and into homes on Thursday in a new round of unusually heavy rains that has killed at least a dozen people in Peru and now threatens flooding in the capital. (Photo by Guadalupe Pardo/Reuters)

Warriors from the Suri tribe in Ethiopia still stage the savage “Donga” battles – even after many fighters have been died from their injuries. Donga stick fights take place after the harvests, the Surmas count days owing to knots on a long stem of grass or jags on the trunk of a tree dedicated to that specific use. Here: A tribeswoman sporting a huge lip plate and wearing a skinned animal carcass on her head. (Photo by Eric Lafforgue/Exclusivepix Media)

A demonstrator catches fire after the gas tank of a police motorbike exploded during clashes in a protest against Venezuelan President Nicolas Maduro, in Caracas on May 3, 2017. Venezuela' s angry opposition rallied Wednesday vowing huge street protests against President Nicolas Maduro' s plan to rewrite the constitution and accusing him of dodging elections to cling to power despite deadly unrest. (Photo by Juan Barreto/AFP Photo)

An injured woman is helped by emergency workers as she lies on the sidewalk in Times Square after a speeding vehicle struck pedestrians on the sidewalk in New York City, U.S., May 18, 2017. A car plowed into a crowd of pedestrians in New York' s bustling Times Square, leaving one person dead and at least 12 other injured in what officials said was an accident. (Photo by Mike Segar/Reuters)

An Iraqi military vehicle passes displaced Iraqi boys returning to their homes in West Mosul's Oreibi neighbourhood after government forces retook control of the area from the Islamic State (IS) group during the ongoing offensive against the jihadists on May 21, 2017. (Photo by Ahmad Al-Rubaye/AFP Photo)

A South China Tiger cub meets public at Guangzhou Zoo on June 22, 2017 in Guangzhou, Guangdong Province of China. Guangzhou Zoo boasts of the successful breeding of South China Tiger cub after 15 years. (Photo by VCG/VCG via Getty Images)

A Common seal named Groot is prepared for release in a transfer cage at Seal Rescue Ireland wildlife sanctuary where two rescued and rehabilitated seals are released back into the sea after months of care in Wexford, Ireland, June 12, 2016. (Photo by Clodagh Kilcoyne/Reuters)

A participant dressed as a mermaid goes to swim in the beach after taking part in the Annual Mermaid Parade in Brooklyn, New York, June 18, 2016. The annual parade, founded in 1983, seeks to bring mythology to life for residents, create confidence in the district and to allow artistic self-expression in public, according to the parade's website. (Photo by Eduardo Munoz/Reuters)