The roommate of the man suspected of shooting two police officers before being shot and killed by other officers Wednesday night in East Boston is speaking out about the moments leading up to the firefight.

Diego, an necn employee who moved to Boston just four months ago, said he was sleeping in his room upstairs on Wednesday night when he heard his two roommates arguing.

The suspect, 33-year-old Kirk Figueroa, was a sworn constable and former Army reservist.

"The way he put it, he was trying to revolutionize the policing world," Diego said.

Additionally, Diego recalls, Figueroa seemed to be racist against white people.

"Race played a big part in Kirk's life. He would constantly talk down on 'white people,'" Diego said. "When he first moved in, he told me, 'Good thing you're Latino ... I would have a problem if you were a white guy.' He tells me, 'I refuse to have a white person sleeping over my head.'"

What ended in chaos, with three people lying shot on the floor of his apartment, at first didn't seem like a major incident to Diego.

"I woke up to them screaming and cursing," he told necn Investigates. "I didn't really think much of it."

Eventually, he said, the screaming died down and he assumed the argument had ended.

"Maybe 10 minutes later, I heard knocking on the front door. I opened my room door and police busted down the front door, guns drawn, saying, 'Hands up! Who are you? What are you doing here?'"

Police said they responded to a 911 call just before 11 p.m. The caller said his roommate, later identified as Figueroa, was threatening him with a knife.

Diego said he was taken outside in his underwear, barefoot, and had no idea what was going on.

Two minutes later, the shooting started.

Two officers had entered the home and were shot by Figueroa, who was then shot and killed by other officers.

"It's hard to describe," Diego said. "It all kind of happened so fast. It took a while to sink in. I see they're lying on the floor. You hear all these gun shots, people screaming, 'Shots fired, shots fired.' The radio is going crazy. You see the helicopter.

"It wasn't until later that I really noticed, I just heard my roommate die. To hear his screams, it's chilling."

Diego told necn investigates that he believes his roommate "snapped" and might have been suffering from post-traumatic stress disorder. Figuero served as an Army reservist from 2003 to 2011 and told his roomates he had an extensive weapons collection.

The two officers he allegedly shot — Richard Cintolo and Matthew Morris — remain in stable but critical condition at Massachusetts General Hospital, but they are expetected to survive.

Diego said he's still shaken by what happened, but is just grateful that no one else was killed.