Newly elected San Francisco District Attorney Chesa Boudin fired multiple prosecutors on Friday afternoon as he reshapes the office and begins implementing his progressive vision two days after being sworn in.

At least six attorneys were fired, possibly more, including several managing attorneys in the office’s criminal division.

“I had to make difficult staffing decisions today in order to put in place a management team that will help me accomplish the work I committed to do for San Francisco,” Boudin said in a statement.

Among those fired, according to multiple sources, were Michael Swart, managing attorney of the office’s Homicide Unit; Todd Barrett and Linda Allen, managing attorneys in the General Felonies Unit; Ana Gonzalez, managing attorney in the office’s Gang Unit; Tom Ostly, a trial attorney in the Crime Strategies Unit, and Kara Lacey, a felony trial attorney.

Several attorneys in the office spoke to The Chronicle on the condition of anonymity because they were not authorized to speak to reporters. The attorneys described a tense afternoon Friday, in which Boudin called the people he fired into his office one-by-one to deliver the news.

The effect on the morale of the other attorneys, they said, was devastating. Many people in the office, though, were relieved to still have jobs, the sources said.

The move was reminiscent of when Terence Hallinan was elected district attorney in 1995 and promptly fired 14 attorneys — or 10% of the 116 prosecutors in the office at the time — after being sworn in. Currently, there are around 135 prosecutors in the office of roughly 300 employees.

But unlike Hallinan, who delivered three-paragraph letters to the attorneys he axed, Boudin fired nearly all of the attorneys face-to-face. Those who had already left the office for the day, he told over the phone.

All of the prosecutors are “at will” employees and not subject to civil service protections. The City Charter allows Boudin to fire them without giving a reason. Some of the fired attorneys, though, said they may pursue legal action.

Some were not surprised by the firings. Boudin ran on a campaign promising to end charging gang enhancements and many observers expected him to disband the Gang Unit, which Gonzalez headed.

Allen prosecuted Jamal Trulove, who was convicted for a 2007 murder and sentenced to 50 years to life. He was later acquitted during a retrial in 2015 and won a $13.1 million settlement from the city after a jury found the officers in the case fabricated evidence and failed to disclose exculpatory evidence.

Boudin brought Trulove in as an adviser during his transition to help create a second look and conviction integrity unit.

Swart is a hard-charging homicide prosecutor known for his brash style in the courtroom. Ostly was an attorney in the Crime Strategies Unit. He was in the middle of prosecuting a multimillion-dollar fencing bust announced last month by interim District Attorney Suzy Loftus.

Boudin was sworn in by Mayor London Breed on Wednesday night and delivered a rousing speech to hundreds of his supporters in which he promised to confront racial disparities in the criminal justice system, work to end mass incarceration, and hold police more accountable in cases of brutality.

He was elected in November in a tight race among four candidates. Boudin, a former deputy public defender, ran the furthest to the left, promising to reshape the city’s legal system.

Boudin also promised to focus on violent crime, leaving many in the office questioning why he let go many of his most experienced felony attorneys.

Evan Sernoffsky is a San Francisco Chronicle staff writer. Email: esernoffsky@sfchronicle.com Twitter: @EvanSernoffsky