Anthony Joshua, right, knocks down Andy Ruiz during the third round of a heavyweight championship boxing match Saturday, June 1, 2019, in New York. Ruiz won in the seventh round. (Photo by Frank Franklin II/AP Photo)

German police officers take pictures as fireworks explode next to the Quadriga sculpture atop the Brandenburg gate during New Year celebrations in Berlin, Germany, January 1, 2017. (Photo by Fabrizio Bensch/Reuters)

Gunfire was brought to the steps of President Truman's Washington home, Blair House, as two assassins tried to kill the chief executive, November 1, 1950. One of the gunmen, Oscar Collazzo of New York, lay wounded at the bottom of Blair House's front steps after the president's police guard had finished their work, at the cost of one guards' life, Dec. 9, 1950. The second gunman was killed. (Photo by Harvey Georges/AP Photo)

Long row of shiny new Flying Fortresses, part of huge reserves being built up in Britain for D-Day, stands by to be flown to combat units as replacements, May 25, 1944. (Photo by AP Photo)

Migrant children run away from clashes with Mexican National Guards after their group crossed the Suchiate River on foot from Guatemala to Mexico, on the riverbank near Ciudad Hidalgo, Mexico, Monday, January 20, 2020. More than a thousand Central American migrants hoping to reach the United States marooned in Guatemala are walking en masse across a river leading to Mexico in an attempt to convince authorities there to allow them passage through the country. (Photo by Santiago Billy/AP Photo)

Chelyabinsk Airport employees take part in an exercise to evacuate aircraft passengers showing symptoms of the 2019-nCoV pneumonia-like coronavirus on February 5, 2020. (Photo by Nail Fattakhov/TASS)

Mothers-to-be show their belly paintings in Hefei, east China's Anhui province on May 8, 2020. (Photo by Rex Features/Shutterstock/China Stringer Network)

Russian Il-76 military transport aircrafts fly in formation during a rehearsal for the flypast, which marks the 75th anniversary of the victory over Nazi Germany in World War Two, in Moscow, Russia on May 4, 2020. The traditional large-scale Victory Day military parade across Red Square was postponed due to the outbreak of the coronavirus disease (COVID 19). (Photo by Maxim Shemetov/Reuters)