Mara Salvatrucha (MS) gang members show off their weapons in the Las Victorias district of San Salvador. In March 2012, the two largest gangs in El Salvador - the Mara Salvatrucha (MS) and the Barrio 18 (M18) - agreed on a truce following secret negotiations between gang leaders in prison which were mediated by a bishop and a former rebel leader. It is unclear whether the decision was the idea of the gangs themselves or whether they were encouraged by the government. (Photo by Adam Hinton)

Actress Tang Wei poses at the “Wu Xia” portrait session during the 64th Annual Cannes Film Festival on May 15, 2011 in Cannes, France. (Photo by Andreas Rentz/Getty Images)

Undated UK Ministry of Defence handout photo of an RAF Tornado GR4 which has been painted in Gulf War “desert pink” paint scheme to honour the aircraft type's almost continuous operational service since the Royal Air Force helped liberate Kuwait from Saddam Hussein's forces, taken by SAC Rose Buchanan, which has been shortlisted for the general public to pick their favourite RAF Image of the Year. (Photo by SAC Rose Buchanan/MoD Crown Copyright/PA Wire)

A young devotee of the Nine Emperor Gods has a large needle pushed through his cheek during the annual Phuket Vegetarian Festival in the southern province of Phuket on October 1, 2016. (Photo by Lillian Suwanrumpha/AFP Photo)

A participant wearing a fantasy costume poses for a picture during the Hero Festival in Marseille, France November 12, 2016. (Photo by Jean-Paul Pelissier/Reuters)

In this photograph taken on October 4, 2016, an Afghan baker prepares bread at his shop as he waits for customers in Lashkar Gah, the capital city of Helmand province. For years Helmand was the centerpiece of the Western military intervention in Afghanistan only for it to slip deeper into a quagmire of instability, with almost the entire southern province teetering on the verge of collapse. Intensified fighting has killed hundreds and forced thousands to flee to besieged capital Lashkar Gah, sparking a humanitarian crisis as the city – one of the last government- held enclaves – risks falling to the Taliban' s repeated ferocious assaults. (Photo by Wakil Kohsar/AFP Photo)

A herder stops for reindeers to have a rest while riding along the tundra area in Nenets Autonomous District, Russia, November 27, 2016. In Russia's remote Arctic regions reindeer herding has been a way of life for centuries. Each winter herders in Russia's sparsely populated Nenets Autonomous District corral their reindeers into open-air pens before selecting weak animals to be culled... (Photo by Sergei Karpukhin/Reuters)

A feminist activist uses a slingshot during a protest against gender violence and patriarchy in Santiago on November 29, 2019. Furious Chileans have since October 18 been protesting social and economic inequality, and against an entrenched political elite that comes from a small number of the wealthiest families in the country, among other issues. (Photo by Javier Torres/AFP Photo)