Volunteers wearing face masks, gloves and protective gear to protect against coronavirus, gather to clean an area of an outdoor book market set up at Red Square with GUM, State Department store, left, St. Basil's Cathedral, center, Spasskaya Tower, second with, and the Kremlin Wall, right, in Moscow, Russia, Saturday, June 6, 2020. Muscovites clad in face masks and gloves ventured into Red Square for an outdoor book market, a small sign of the Russian capital's gradual efforts to open up amid coronavirus concerns. (Photo by Alexander Zemlianichenko/AP Photo)

South Korean Lee Jung-sook (L), 68, wipes the tears from her North Korean father Lee Heung-jong, 88, as they bid each other a sad farewell at a resort on Mount Kumgang, North Korea, 22 October 2015. About 390 South Koreans arrived at the resort two days ago for the first face-to-face reunion of families separated by the 1950-53 Korean War in nearly 20 months. A second group of some 260 South Koreans will do the same for three days starting on 24 October. (Photo by Yonhap/EPA)

A protester with his face smeared with soot from burning barricades stands in the Musaga neighbourhood of Bujumbura on May 6, 2015. Government and opposition rivals are meeting in Burundi in a bid to end deadly demonstrations against a third term bid by the president, as regional foreign ministers arrived to add pressure. (Photo by Phil Moore/AFP Photo)

Julian, left, is photographed by his mother with friend Gianluca, right, under water at a public pool in Gelsenkirchen, Germany, on a hot Friday, July 3, 2015. Germany faces a heat wave with temperatures up to 38 degrees Celsius (100 degrees Fahrenheit) at the weekend. (Photo by Martin Meissner/AP Photo)

Indian dancers paint their body like tigers as they perform a Tiger dance during the International day of the Tiger in Calcutta, India, July 29, 2015. Students of Calcutta are taking part in an awareness campaign aiming to draw attention to the threats that tigers face due to habitat loss and poaching. (Photo by Piyal Adhikary/EPA)

A girl with her face painted to look like the popular Mexican figure called "Catrina", jumps as she takes part in the annual Catrina Fest in Mexico City November 1, 2015. (Photo by Carlos Jasso/Reuters)

UFC women's bantamweight champion Holly Holm and Miesha Tate face off during the UFC 196 weigh ins at the MGM Grand Garden Arena in Las Vegas on Friday, March 4, 2016. (Photo by L.E. Baskow/Las Vegas Sun via AP Photo)

In this Monday, March 10, 2014 photo, a 9,000 year-old mask is on display at the Israel Museum in Jerusalem. The exhibition called “Face To Face” shows eleven stone masks, said to have been discovered in the Judean desert and hills near Jerusalem, which date back 9,000 years and offer a rare glimpse at some of civilization's first communal rituals. (Photo by Tsafrir Abayov/AP Photo)