Men cover their heads from the sun while riding on a motorcycle during a hot day in Cairo, Egypt, August 17, 2015. A heatwave killed at least 61 people across Egypt from Sunday to Tuesday and caused nearly 600 people to be admitted to hospital, Egypt's health ministry said on state news agency MENA on Wednesday. (Photo by Amr Abdallah Dalsh/Reuters)

A drone operated by paramilitary police flies over the site of last week's explosions at Binhai new district in Tianjin, China, August 17, 2015. Many operations have resumed at China's Tianjin port, trade sources said, after explosions last week that killed more than 100 people and disrupted business at what is an important oil, gas and bulk import harbor for Asia's biggest economy. The explosions on August 12 led to the disruption of all chemical and oil tanker discharges at the port, and imports of iron ore were also affected. (Photo by Kim Kyung-Hoon/Reuters)

A Japanese Ground Self-Defense Force Type 92 Mine sweeping vehicle fires a rocket behind a Type 74 armoured tank during an annual training session, which is based on a scenario to defend or retake islands in Japanese territory, near Mount Fuji at Higashifuji training field in Gotemba, west of Tokyo, August 18, 2015. (Photo by Yuya Shino/Reuters)

Guests have breakfast as another guest climbs to gather at the Skylodge Adventure Suites in the Sacred Valley in Cuzco, Peru, August 14, 2015. Tourists taking on an arduous climb up the steep cliff face of Peru's Sacred Valley are being rewarded for their efforts by being able to spend the night in transparent mountaintop sleeping pods at the “Skylodge Adventure Suites”. To reach the pods, visitors need to climb 400 metres of via ferrata (a steel cable and rungs) up the valley side or hike an intrepid trail through zip lines. (Photo by Pilar Olivares/Reuters)

A giant panda cub is pictured in an incubator at the Ya'an Bifengxia Giant Panda Breeding and Research Center in Ya'an city, southwest China's Sichuan province, 21 August 2015. Ten tiny panda cubs made their first public appearance at China's Ya'an Bifengxia Giant Panda Breeding and Research Center in southwestern Sichuan province on Friday (21 August 2015). All of the ten giant pandas were born in 2015. The oldest of them is just two month old, while the youngest one was born a week ago. This marks the first time they were put together as a group since they were born. (Photo by Imaginechina/Splash News)

Alkar Vito runs during the Children's Alka competition in Vuckovici village, Croatia, August 23, 2015. Children's Alka is a tournament which has been held every August in the Croatian village of Vuckovici since 1955, commemorating the victory over the Ottoman Turkish administration. The tournament is named after the ring, Alka, which children have to hit with their spears. (Photo by Antonio Bronic/Reuters)

Children fall as they slide down on a float along a chute to cross a pool of water and foam during the “Letniy Gornoluzhnik” (Summer mountain puddle rider) festival at the Bobroviy Log Fun Park near the Siberian city of Krasnoyarsk, Russia, August 23, 2015. The annual competition marks the end of the summer season at the Siberian ski, rest and entertainment resort. (Photo by Ilya Naymushin/Reuters)

A group of people wearing full solid-coloured bodysuits walk along a promenade as they take part in a street art performance in Bat Yam, near Tel Aviv, Israel August 29, 2015. Some 40 people participated on Saturday in the performance, initiated by a group of artists called Prizma Ensemble, as part of the city's annual international street art and street theatre festival. The group says the performance deals with concepts of identity and movement in public spaces. (Photo by Amir Cohen/Reuters)