BOSTON – Excerpts from James “Whitey” Bulger’s FBI informant file presented to the jury at his racketeering trial Monday show Bulger secretly provided information on a variety of criminals, from members of the Italian Mafia to people in his own South Boston neighborhood.

Bulger, 83, is on trial, accused of playing a role in 19 killings during the 1970s and ’80s while allegedly leading the Winter Hill Gang.

His lawyers have strongly denied that he was an FBI informant. Instead, they say, he paid certain FBI agents for information that would help him and his gang, including tipoffs on investigations and indictments.

At one point Monday, Bulger appeared to be visibly angry during arguments between his lawyer and the prosecution outside earshot of the jury. Several people heard him mutter an expletive and deny that he was an informant.

The jury spent the day listening to James Marra, a special agent with the Justice Department’s Office of the Inspector General, read excerpts from Bulger’s 700-page FBI file.

Marra said file documents show that Bulger began working as an informant in 1971, but was shut down after a short time after his FBI handler determined he was not providing useful information. Marra said Bulger became an informant again in 1975 for then-FBI Agent John Connolly and continued in that role almost continually for about 15 years, until Connolly retired.

Connolly was later convicted of racketeering for warning Bulger and his gang of an upcoming indictment, prompting Bulger to flee. Bulger was one of the nation’s most wanted fugitives for more than 16 years when he was finally captured in Santa Monica, Calif., in 2011.

Marra read reports written by Connolly and several supervisors at the FBI in which they described meetings they had with Bulger and information he gave them about criminal activity ranging from drug trafficking to murder.

Marra was asked to read several reports Connolly wrote about what Bulger allegedly told him about the killing of Edward “Brian” Halloran in 1982.

Prosecutors say Bulger and an associate gunned down Halloran after Connolly told him Halloran was talking to the FBI about Bulger’s role in the 1981 killing of an Oklahoma businessman. But in his conversations with Connolly, Bulger said he had heard on the street that the Mafia had killed Halloran. He later gave Connolly the names of some criminals from Boston’s Charlestown neighborhood he suggested may have killed Halloran.