An Israeli army officer gives explanations to journalists during an army organised tour in a tunnel said to be used by Palestinian militants for cross-border attacks, July 25, 2014. (Photo by Jack Guez/Reuters)

Labourers work at the installation site of Liquefied Petroleum Gas (LPG) pipeline on May Day or Labour Day in Chandigarh, India, May 1, 2015. (Photo by Ajay Verma/Reuters)

Russia's Ekaterina Birlova casts a shadow on the sand as she serves to Poland during a women's beach volleyball match at the 2016 Summer Olympics in Rio de Janeiro, Brazil, Tuesday, August 9, 2016. (Photo by Marcio Jose Sanchez/AP Photo)

New Orleans police officers try to keep their heads down as they move in on a Black Panther headquarters during an exchange of gunfire in New Orleans on September 15, 1970. The shootout occurred as police moved in to make arrests on Tuesday morning following a series of incidents. (Photo by Jack Thornell/AP Photo)

A boy collects drinking water from a hand pump in Kutubdia, Bangladesh on March 30, 2016. Kutubdia is one of many islands affected by some of the fastest recorded sea-level rises in the world. The island has halved in size in 20 years. (Photo by SIipa/Rex Features/Shutterstock)

A girl collects water lily flowers at a pond in Kampong Speu province Cambodia, March 24, 2017. Picture taken March 24, 2017. (Photo by Samrang Pring/Reuters)

In this Sunday, June 27, 2010 file photo two men compete in an ostrich race at Highgate ostrich farm in Oudtshoorn, South Africa. Clambering onto an ostrich for a ride used to be popular among tourists in a South African town of Oudtshoorn known of as the “ostrich capital of the world”. Not so much anymore. Two major ostrich farms in Oudtshoorn have stopped offering ostrich rides to tourists, responding to concerns about the birds’ welfare. A third farm is sticking with the feature, saying it is regulated and that ostriches do not experience discomfort. The Highgate farm, however, continues to offer ostrich rides. (Photo by Shuji Kajiyama/AP Photo)

In this photo taken late Thursday, May 7, 2015, a prison guard, left, and seated inmates cast shadows on a wall while waiting for the beginning of a rock concert by Romanian band Pro Musica, inside the Popa Sapca jail in Timisoara, western Romania. (Photo by Adi Piclisan/AP Photo)