ORLANDO, Fla. (AP) -- Fearing imminent arrest in a triple slaying, Ibragim Todashev started acting suspiciously. His mood, once cooperative with investigators, became agitated. His eyes darted around his small apartment in Florida, as if he were looking for a weapon or a way out.
As Todashev wrote a statement about his role in the 2011 killings in Waltham, Mass. -- slayings that received renewed attention after the Boston Marathon bombing -- a state trooper sent an ominous text message: "Be on guard. He is in vulnerable position to do something bad. Be on guard now."
Moments later, Todashev, a friend of one of the Boston marathon bombing suspects, flipped a coffee table in the air, knocking down an FBI agent in the room and causing a gash on his head. Todashev then grabbed a broomstick or mop handle and charged toward the Massachusetts trooper. The FBI agent shot Todashev several times, killing him last May, according to two reports Tuesday that provided the first clear picture of the shooting and cleared the agent of any charges.
In the Florida report, prosecutor Jeff Ashton noted Todashev's experience as a mixed martial arts fighter.
"The one common thread among all was the observation that he was, at his core, a fearless fighter," Ashton said in a letter to FBI Director James Comey. "Perhaps on this occasion, he simply reverted to that basic aspect of his personality and chose to go down fighting."
Separately, the Justice Department echoed the Florida findings. "To emphasize, these prosecutorial decisions were made independent of the FBI," bureau spokesman Mike Kortan said.
The shooting happened May 22, about a month after the April 15 marathon bombings. Investigators were looking into the background of bombing suspect Tamerlan Tsarnaev, who was killed four days after the marathon in a shootout with police, when they learned of his friend, Todashev. Both were Chechen and trained together in Boston. Tsarnaev was a heavyweight boxer.
It wasn't long before authorities focused on whether the men had any involvement in the Waltham killings. In that case, three men were found in an apartment with their necks slit and their bodies reportedly covered with marijuana. One of the victims was a boxer and Tsarnaev's friend.
Friends of the men have said they presumed the killings were drug-related, but police never confirmed that and the investigation is ongoing.
Federal authorities have said in court filings that Todashev also implicated Tsarnaev in the slayings, but the Justice Department report said the details of the confession were not being released publicly at the request of Massachusetts prosecutors.
Investigators had questioned Todashev several times in the weeks before he was killed. They had watched videos of his MMA fights and recognized his quick temper, in part because of a previous road rage episode, according to the reports.
On the day of the shooting, they had questioned him for almost five hours. The FBI agent and two Massachusetts troopers felt they were making progress, and one trooper texted to a prosecutor in Massachusetts that Todashev had admitted to his role in the slayings. "Who's your daddy?" the trooper said in a text.
But Todashev's mood changed, and the trooper removed a sword hanging on the wall of the apartment.
After Todashev waived his Miranda rights, he started writing on a white legal pad.
"'Okay. I'm going to tell you I was involved in it,'" Todashev told the investigators, according to an FBI chronology cited in the Florida report.
One of the troopers stepped outside to call a prosecutor in Massachusetts, who was on his way into the office to draft an indictment.
That's when Todashev flipped the table, and he "moved incredibly quickly" the trooper in the room told investigators. Todashev grabbed the handle, stood in a fighting position and "charged toward me as if he was going to impale me with the pole," the trooper said.
The FBI agent told investigators, "There was no doubt in my mind that Todashev intended to kill us both."
An autopsy showed Todashev was shot once in the head and six times in the torso.
Todashev's family has raised doubts about the account provided by law enforcement, saying that Todashev was recovering from knee surgery and limping at the time he was killed.
Richard Wallsh, the executive director of the State Attorney's Office said Todashev appeared to have recovered from the surgery based on a video taken by FBI agents while they were following Todashev in the weeks prior to the shooting. The FBI video captured Todashev beating up two men in a dispute over a parking spot at an Orlando shopping center.