A brown bear waits for food at the zoo in Madrid, Spain on July 30, 2016. (Photo by Jorge Sanz/Pacific Press/SIPA Press/Rex Features/Shutterstock)

A police officer detains a woman on suspicion of collaborating with the 18th street gang during a "Safe House" operation at the Concepcion neighbourhood in San Salvador, July 2, 2015. Salvadoran police make “Safe House” operations at dangerous neighbourhoods of the capital to prevent murders, according to local media. (Photo by Jose Cabezas/Reuters)

South Korea's Black Eagles aerobatics team performs an aerial display forming a Ying and Yang logo during the Singapore Airshow at Changi exhibition center in Singapore on February 16, 2016. (Photo by Roslan Rahman/AFP Photo)

Expedition 44 flight engineer and NASA astronaut Scott Kelly seen inside the Cupola, a special module which provides a 360-degree viewing of the Earth and the International Space Station. Kelly is one of two crew members spending an entire year in space. (Photo by Scott Kelly/NASA)

People wash in water from a broken water pipeline on the outskirts of Kolkata, India, March 30, 2016. (Photo by Rupak De Chowdhuri/Reuters)

Subway passengers walk past bronze sculptures representing the Soviet people at the Ploshchad Revolyutsii metro station in Moscow, on November 14, 2012. The station was opened in 1938. (Photo by Kirill Kudryavtsev/AFP Photo)

North Korea's Samjiyon Orchestra performs at Pyongyang Grand Theatre in Pyongyang, North Korea, September 18, 2018. (Photo by Pyeongyang Press Corps/Pool via Reuters)

A girl shows a fish she has caught in a bare- hand fish catching contest held in Housangyuan Village of Lyutan Township Wuyi County, east China' s Zhejiang Province, September 23, 2018. People across China hold various activities to celebrate the country' s first Farmers' Harvest Festival, which falls on Sept. 23 this year. (Photo by Zhang Jiancheng/Xinhua News Agency/Barcroft Images)