Sukhoi Su-30SM jet fighters of the Russkiye Vityazi (Russian Knights) aerobatic team perform during a demonstration flight in Krasnoyarsk, Russia October 6, 2018. (Photo by Ilya Naymushin/Reuters)

Militants loyal to Yemen's exiled government ride on the back of a pick-up truck in the country's central city of Taiz August 19, 2015. Militia forces loyal to Yemen's exiled government fought their way deep into the central city of Taiz this week, local officials said, largely pushing out Houthi militiamen from the country's third largest city. (Photo by Reuters/Stringer)

A Munduruku Indian child is pictured at the Planalto Palace, where a meeting with Minister of the General Secretariat of the Presidency of Brazil Gilberto Carvalho was being held with other Munduruku Indians, in Brasilia, June 4, 2013. President Dilma Rousseff's government sought on Tuesday to defuse mounting conflicts with indigenous groups over its decision to stop setting aside farm land for Indians and plans to build more hydroelectric dams in the Amazon. The government flew 144 Munduruku Indians to Brasilia for talks to end a week-long occupation of the controversial Belo Monte dam on the Xingu river, a huge project aimed at feeding Brazil's fast-growing demand for electricity. (Photo by Ueslei Marcelino/Reuters)

A Felix Airways plane is seen after it was destroyed by an airstrike at the international airport of Yemen's capital Sanaa, April 29, 2015. Jets from a Saudi-led alliance destroyed the runway of Yemen's Sanaa airport on Tuesday to prevent an Iranian plane from landing there, Saudi Arabia said, as fighting across the country killed at least 30 people. Airport officials said the strikes set a civilian aircraft operated by Yemeni Felix Airways ablaze. (Photo by Khaled Abdullah/Reuters)

An Indonesian man displays his collection of rings with various gemstones at an exhibition and competition of the best gemstone at a mall in Jakarta on August 6, 2015. The recent fad of collecting rings with precious gemstone or polished gemstone locally called “batu akik” is sweeping across Indonesia, with collectors going for the very rare stones and it's possession many believe will give the owner supernatural power. (Photo by Bay Ismoyo/AFP Photo)

A flood affected family moves on a banana raft past a fishing net in Morigaon district, east of Gauhati, northeastern Assam state, India, Sunday, July 31, 2016. A week of heavy rain has killed dozens of people and uprooted tens of thousands of others from their homes. Floods are an annual occurrence in Assam and many parts of India during the June-September monsoon season. (Photo by Anupam Nath/AP Photo)

Musafir, a pet monkey, eats sweets on a pavement in Kolkata, India, June 9, 2016. (Photo by Rupak De Chowdhuri/Reuters)

A young girl plays on the glass bottom platform of the Oriental Pear TV Tower as she travels with her family on the second day of the Chinese Lunar New Year holiday, also known as Spring Festival, in Shanghai, China on February 18, 2018. Some 287 million tourists travelled in China during the first four days of the week-long Chinese Lunar New Year holiday, up 11.1 percent from the same period last year, new data showed Sunday. (Photo by Imaginechina/Rex Features/Shutterstock)