A man celebrates the start of the New Year, backdropped by fireworks exploding in the background over Copacabana Beach in Rio de Janeiro, Brazil, Saturday, January 1, 2022. (Photo by Bruna Prado/AP Photo)

An unknown number of guns are being built with the mechanisms, causing problems for the police and ATF officials. Photo: An ATF agent holds a generic unfinished receiver, back, and one that has been manufactured, front, at an ATF field office in Washington, on May 06, 2014. The ATF is trying to crack down on the trade in the makeshift guns by targeting shops and individuals who offer to turn the unfinished receivers into functional pieces for firearms. (Photo by Bill O'Leary/The Washington Post)

A competitor participates in the Tough Mudder challenge near Henley-on-Thames in southern England May 2, 2015. (Photo by Eddie Keogh/Reuters)

Deadwood is pictured in the onetime spa and resort town Epecuen, November 5, 2015. Over the past few years the town of Epecuen, located 550 km (341 miles) southwest of Buenos Aires, has been attracting tourists with its eerie apocalyptic atmosphere after a flood submerged it in salt water for more than two decades. Photo by Enrique Marcarian/Reuters)

Visitors walk past a train-shaped ice sculpture ahead of the 31st Harbin International Ice and Snow Festival in the northern city of Harbin, Heilongjiang province, January 4, 2015. The winter festival will be officially opened on January 5, 2015. (Photo by Kim Kyung-Hoon/Reuters)

Competitors in the Pro Bikini division pose during the Arnold Classic Australia at The Melbourne Convention and Exhibition Centre on March 14, 2015 in Melbourne, Australia. (Photo by Robert Cianflone/Getty Images)

A woman waits at a polio immunisation health centre, in Maiduguri, Borno State, Nigeria, August 29, 2016. Nigeria's military has liberated large swathes of land from Boko Haram but a ride with an army convoy, all guns firing for fear of ambush, shows how far the northeast is from normality after a brutal Islamist insurgency that has displaced millions. (Photo by Afolabi Sotunde/Reuters)

In this photo taken Sunday, May 6, 2012, Denis Lutskevich, left, is detained by police during an opposition rally in Bolotnaya Square in Moscow. The former naval cadet and first-year student, 21-year-old Lutskevich was attending his first protest when he was detained, and is still in prison Monday May 6, 2013, on the first year anniversary of the protest. (Photo by Pavel Golovkin/AP Photo)