London’s police force said Sunday that some officers are refusing to conduct armed patrols after a colleague was charged with murder in the fatal shooting of an unarmed Black man.

A Metropolitan Police marksman was charged Wednesday over the September 2022 death of Chris Kaba, 24. Kaba was killed after officers in an unmarked vehicle pursued and stopped the car he was driving. He was struck by a single bullet fired through the windshield as he sat in the Audi car.

Kaba’s family welcomed the murder charge against the officer, who has not been publicly named. He was granted conditional bail and is expected to stand trial next year.Only about one in 10 of London’s police officers carry firearms, and the ones that do undergo special training.

The Metropolitan Police force said Sunday that “a number of officers have taken the decision to step back from armed duties while they consider their position.” It said officers were concerned that the murder charge “signals a shift in the way the decisions they make in the most challenging circumstances will be judged.”

The BBC said more than 100 officers had turned in their firearm permits and that police from neighboring forces were called in to help patrol London on Saturday night.

The force said it still had “significant firearms capability,” but had asked the Ministry of Defense to provide assistance with “counterterrorism support should it be needed.”

The request means soldiers could be called on to do specific tasks the police are unable to perform, but they won’t perform routine police work or have the power of arrest.

Home Secretary Suella Braverman, who is in charge of policing for the U.K.’s Conservative government, said she would review armed policing to ensure that armed officers “have the confidence to do their jobs.”

“In the interest of public safety, they have to make split-second decisions under extraordinary pressures,” Braverman posted on X, formerly known as Twitter. “They mustn’t fear ending up in the dock for carrying out their duties. Officers risking their lives to keep us safe have my full backing, and I will do everything in my power to support them.”

Fatal shootings by police in the U.K. are rare. In the year to March 2022, armed officers in England and Wales fired weapons at people four times, according to official statistics.

It is also extremely rare for British police officers to be charged with murder or manslaughter over actions performed while they were on duty.

In one of the few cases in recent years, a police constable was sentenced in 2021 to eight years in prison for the killing of Dalian Atkinson, a former professional soccer player who died after being shot by a stun gun and kicked in the head during an altercation. The officer, Benjamin Monk, was cleared of murder but convicted of manslaughter.

Kaba’s shooting came amid intense scrutiny of the Metropolitan Police.

In 2021, an officer pleaded guilty to kidnapping, raping, kidnapping and killing Sarah Everard, a 33-year-old woman who disappeared while walking home from visiting a friend. Another officer, who worked in the same parliamentary and diplomatic protection unit, pleaded guilty in January to committing dozens of rapes between 2003 and 2020.

In March an independent review found the London force had lost public confidence because of deep-seated racism, misogyny and homophobia.

The force says it is committed to rooting out misconduct, and has dismissed about 100 officers for gross misconduct over the past year. But it said last week it could take years to remove all corrupt officers.