Revellers enjoying the pubs and clubs in Leeds despite concerns over Omicron on December 10, 2021. Festive revellers have hit the pubs and clubs across the UK tonight as Plan B rules come into force and fears grow over the spread of Omicron. (Photo by Nb press ltd)

Over 30 Douglas C-47 Skytrains (Dakotas) making final preparations for flight formation practice before the 75th D-Day Anniversary flight to Normandy in Duxford, England on June 4, 2019. (Photo by UK Air Force Images)

American soldiers leaping from an armoured personnel carrier during exercises in Korea, 17th March 1954. (Photo by Three Lions)

Pope Francis attends a circus performance during his weekly general audience at Paul VI hall on December 22, 2016 at the Vatican. (Photo by Alberto Pizzoli/AFP Photo)

Medic James E. Callahan of Pittsfield, Mass., gives mouth-to-mouth resuscitation to a dying soldier in war zone D, about 50 miles northeast of Saigon, June 17, 1967. Thirty-one men of the 1st Infantry Division were reported killed in the guerrilla ambush, with more than 100 wounded. (Photo by Henri Huet/AP Photo)

Even upside down, a stereophonic turntable continues to play and hold the interest of Helen Sorowitz, a visitor to the New York High Fidelity Show in New York, September 9, 1960. (Photo by Ruben Goldberg/AP Photo)

A member from the Iraqi security forces beats an Islamic State insurgent, who was captured in Tikrit April 1, 2015. Iraqi troops and Shi'ite paramilitary fighters were battling Islamic State on Wednesday in northern Tikrit, which officials described as the Sunni Muslim militant group's last stronghold in the city. (Photo by Alaa Al-Marjani/Reuters)

Devotees wearing personal protective equipment (PPE), carry a chariot of Pachali Bhairab amid the spread of coronavirus disease (COVID-19), in Kathmandu, Nepal on October 21, 2020. (Photo by Navesh Chitrakar/Reuters)