On Wednesday, notorious Boston gangster and hit man Stephen “The Rifleman” Flemmi took the stand at Boston’s Moakley Federal Courthouse to testify against former New England Mafia boss Frank Salemme, accused of murder.

Flemmi, himself serving a life sentence having pled guilty to ten murders among other crimes, testified that some of those murders had been carried out at Salemme’s behest.

But before prosecutors could get to that part of the story, Flemmi’s testimony took an unexpected turn after U.S. Attorney Fred Wyshak asked Flemmi an almost pro-forma question.

“I want to ask you about a man named Frank Salemme,” Wyshak began. Then he asked Flemmi if he saw Salemme in the courtroom.

The 83-year old Flemmi looked around the room, his gaze sweeping past Salemme, 84 years old and frail in appearance, who sat in the front of the courtroom in plain view.

Flemmi said he did not see Salemme. Wyshak asked him to look again. Flemmi stood, and looked again.

“I would recognize him if I see him,” he said, still looking around the room, as if Salemme might be standing unnoticed in some corner. “But if I don’t see him, I don’t see him.”

It didn’t appear to be a ruse.

“When was the last time you saw Frank Salemme,” Wyshak asked, perhaps more for the jury’s sake than anything else.

“Maybe nineteen … nineteen ninety-three,” Flemmi answered sitting back down to testify against the man he could no longer see.

Salemme and co-defendant Paul Weadick are accused of the 1993 murder of Massachusetts club owner Stephen DiSarro, one-time owner of The Channel rock club in South Boston.

Prosecutors say that Salemme ordered DiSarro, who was under investigation for bank fraud at the time, killed to prevent him from informing; and that Weadick and Salemme’s son, Frank Jr., now deceased carried out the murder by strangling DiSarro at Salemme’s home while Salemme looked on.

Prosecutors told jurors in opening statements that Flemmi will testify to having been an eye witness to DiSarro’s murder – the only eye witness, defense lawyers emphasized.

And defense lawyers are sure to spend much of their cross-examination focusing on the deal Flemmi made with prosecutors in agreeing to cooperate in this case: Flemmi will avoid the death penalty for his testimony.

And he’ll likely be allowed to live out his life sentence in a specialized witness protection service within the federal prison system.

Flemmi has yet to testify about DiSarro’s murder.

But on Wednesday his testimony began with an acknowledgement of various other murders he said he committed – some of them at Salemme’s behest.

That testimony will presumably go toward the prosecution’s argument that Salemme had the authority, experience and willingness to order executions.

At one point, Flemmi described helping Salemme plant a bomb in the car of an attorney, John Fitzgerald, whose client was testifying against members of the New England mob.

The bomb went off but did not kill Fitzgerald, and Flemmi, Salemme and another associate, Peter Poulos fled the state, eventually making their way to Los Angeles.

On the stand, Flemmi said that at some point Salemme left – but was still calling the shots:

Prosecutor Fred Wyshak: What happened to Peter Poulos?

Stephen Flemmi: He was murdered.

Wyshak: By who?

Flemmi: By me … Frank insisted, because he was part of the bombing.

Wyshak: You shot him?

Flemmi: Yes.

Wyshak: What did you do with his body?

Flemmi: Dumped him by the side of the road and left him there.

Wyshak’s questioning went on to elicit another pattern relevant to Salemme’s alleged ordering DiSarro killed as DiSarro felt pressure from the FBI to inform on Salemme.

Wyshak: Why would you shoot one of your criminal colleagues?

Flemmi: Well, because of the fact that he was a witness. … we felt, he wouldn’t be able to stand up to pressure in court.

Wyshak: What does that mean, ‘not be able to stand up?’

Flemmi: Well, if the police got a hold of him that he would cooperate with them.