Police officers escort people from inside the shopping center as they respond to a shooting at the Olympia Einkaufzentrum (OEZ) at July 22, 2016 in Munich, Germany. According to reports, several people have been killed and an unknown number injured in a shooting at a shopping centre in the north-western Moosach district in Munich. Police are hunting the attacker or attackers who are thought to be still at large. (Photo by Joerg Koch/Getty Images)

In this Monday, July 25, 2016 photo, skydiver Luke Aikins smiles as he jumps from a helicopter during his training in Simi Valley, Calif. After months of training, this elite skydiver says he's ready to leave his chute in the plane when he bails out 25,000 feet above Simi Valley on Saturday. That's right, no parachute, no wingsuit and no fellow skydiver with an extra one to hand him in mid-air. (Photo by Jae C. Hong/AP Photo)

A child plays in front of “Etnias”, a large graffiti wall by Brazilian graffiti artist Eduardo Kobra created ahead of the Rio 2016 Olympic Games at Porto Maravilha in Rio de Janeiro, Brazil, 30 July 2016. The Olympics start on 05 August. Eduardo Kobra hopes to set a Guinness World Record for the largest graffiti created by a single artist. (Photo by Lukas Coch/EPA)

A man poses for a photograph in front of a mural of Democrat US presidential nominee Hillary Clinton clad in a swimsuit bearing the colours of the US flag in West Footscray in Melbourne on July 30, 2016. An Australian mural of US presidential nominee Hillary Clinton in a revealing, stars and stripes swimsuit may be taken down, after it has reportedly been deemed offensive. (Photo by Paul Crock/AFP Photo)

A combination photo shows various popular street foods under $6 from various hawker food stalls and eateries in Singapore, taken between July 28 to 31, 2016. Top row (L to R) bak chor mee, soya sauce chicken; Middle row (L to R) laksa, hokkien mee, nasi lemak, ice kachang; Bottom row (L to R) rojak, roti prata and satay. (Photo by Edgar Su/Reuters)

Bar girls entertain Indian men at a bar along the Walking Street where bars and sеx scenes are a commonplace July 31, 2016 in Pattaya, Thailand. Thailand's first female minister of tourism would like the sеx trade that is a huge business in the country to be banned. Tourists flock to Thailand for many sights including beautiful beaches but also for sеx tourism. Cities like Bangkok and Pattaya are well known as hubs of the Southeast Asian sеx trade, despite the fact that prostitution has been illegal in Thailand since 1960. (Photo by Paula Bronstein/Getty Images)

People try to catch offerings thrown off the summit of Mount Bromo volcano by Tengger tribe members and local tourists in Probolinggo, East Java province on July 18, 2019, as part of the Yadnya Kasada Festival. During the annual Yadnya Kasada festival, the Tenggerese climb Mount Bromo, an active volcano, and seek the blessing from the main deity by presenting offerings of rice, fruit, livestock and other items. (Photo by Juni Kriswanto/AFP Photo)

Comandos de Salvamento rescuers Maria Martinez (L) and Ana Chichilla attend to a wounded homeless man in San Salvador, El Salvador July 16, 2016. The man was attacked with a machete by suspected gang members. In 2015, El Salvador registered a record 103 homicides per 100,000 habitants, making it one of the most dangerous countries in the world outside a war zone. But for many young people who have few chances to distance themselves from rivalries between so-called maras in their schools and neighbourhoods, a civil-society organisation called the Comandos de Salvamento, or Rescue Corps, has been a refuge. (Photo by Jose Cabezas/Reuters)