A police officer who was injured when falling of a horse during scuffles with demonstrators at Downing Street during a Black Lives Matter march in London, Saturday, June 6, 2020, is dragged by colleagues, as people protest against the killing of George Floyd by police officers in Minneapolis, USA. Floyd, a black man, died after he was restrained by Minneapolis police while in custody on May 25 in Minnesota. (Photo by Frank Augstein/AP Photo)

Girls refresh themselves and their dog with water spray frames set along the central street of the Ukrainian capital of Kiev during a heatwave on June 25, 2020. (Photo by Sergei Supinsky/AFP Photo)

Young children at a Bristol, Great Britain health centre unsure of the benefits of sun-lamps and the special glasses that must be worn, July 1948. The health centre was part of the newly introduced free National Health Service. (Photo by Popperfoto/Getty Images)

An opposition fighter from the Failaq al-Rahman brigade fires a heavy machine gun in Jobar, a rebel-held district on the eastern outskirts of the Syrian capital Damascus, on March 19, 2017. (Photo by Amer Almohibany/AFP Photo)

A reveller catches beer thrown from a balcony during the opening day or “Chupinazo” of the San Fermin Running of the Bulls fiesta on July 6, 2017 in Pamplona, Spain. The annual Fiesta de San Fermin, made famous by the 1926 novel of US writer Ernest Hemmingway entitled “The Sun Also Rises”, involves the daily running of the bulls through the historic heart of Pamplona to the bull ring. (Photo by Pablo Blazquez Dominguez/Getty Images)

Veteran cholita wrestler Jennifer dos Caras, 45, holds a cement block over teen wrestler Lucero la Bonita in the ring in El Alto, Bolivia, Monday, January 21, 2019. Trainees of cholita wrestling are still a year away from their full professional debuts while competing in matches against established athletes. (Photo by Juan Karita/AP Photo)

A fisherman sorts his net next to the 37-meter-long “KAWS:HOLIDAY Companion” inflatable sculpture in Tsing Yi, Hong Kong, China, 21 March 2019. KAWS:HOLIDAY, made by US artist and designer Brian Donnelly known professionally as Kaws, will be displayed in Hong Kong's Victoria Harbour from 22 to 31 March 2019. (Photo by Jerome Favre/EPA/EFE)

A staff member demonstrates how she puts on the helmet of a mock space suit at the C-Space Project Mars simulation base in the Gobi Desert outside Jinchang, Gansu Province, China, April 17, 2019. The facility – comprising several interconnected modules including a greenhouse and a mock decompression chamber – opened its doors to the public. (Photo by Thomas Peter/Reuters)