Men wearing costume of traditional firefighters perform acrobatic stunts atop a bamboo ladder following a memorial service for firefighters at Sensoji temple in Tokyo's downtown of Asakusa May 25, 2015. Hundreds of firefighters in traditional costume gathered on Monday for the memorial service for firefighters who were killed performing their duties during the past 300 years. (Photo by Issei Kato/Reuters)

The mother (2nd R) of missing firefighter Xue Ning is helped by other family members as she cries outside the venue of a news conference after trying to demand for more information from government officials, following the explosions on Wednesday night at Binhai new district in Tianjin, China, August 15, 2015. (Photo by Jason Lee/Reuters)

A picture shows the blood stained floor of a kindergarten following reported shelling in the rebel-held area of Harasta, on the northeastern outskirts of the capital Damascus, on November 6, 2016. At least four children were killed and 19 people injured in the government strike in Harasta, according to the Syrian Observatory for Human Rights. (Photo by Sameer Al-Doumy/AFP Photo)

Syrian civil defence volunteers, known as the White Helmets, rescue a boy from the rubble following a reported barrel bomb attack on the Bab al- Nairab neighbourhood of the northern Syrian city of Aleppo on November 24, 2016. (Photo by Ameer Alhalbi/AFP Photo)

Ladies enjoyed themselves last night – while keeping safe with their face masks on in Liverpool, United Kingdom on Saturday, December 5, 2020, after coronavirus restrictions were eased following the end of the second national lockdown. (Photo by London News Pictures)

Undercover Israeli police arrest a Palestinian demonstrator during clashes following protests against U.S. President Donald Trump's decision to recognize Jerusalem as the capital of Israel, in the West Bank city of Ramallah, Wednesday, December 13, 2017. (Photo by Nasser Shiyoukhi/AP Photo)

A counter-protester grabs the flag of a pro-police demonstrator during a rally, following weeks of protests against racial inequality in the aftermath of the death in Minneapolis police custody of George Floyd, in Boston, Massachusetts, U.S. June 27, 2020. (Photo by Brian Snyder/Reuters)

A showgirl in a face mask stands by the door at the reopening of Bally's Las Vegas hotel and casino, Thursday, July 23, 2020, in Las Vegas. The casino reopened for the first time since March following a closure to prevent the spread of the coronavirus. (Photo by John Locher/AP Photo)