Last Updated Jun 8, 2015 4:44 PM EDT
BOSTON -- Surveillance video released Monday of the fatal shooting of a Boston man suspected of plotting to kill police officers shows six plainclothes officers surrounding him before opening fire in a parking lot.
The blurry video shows Usaamah Rahim, 26, walking through a CVS parking lot on his way to a bus stop in the city's Roslindale neighborhood during the early morning hours of June 2.
Officers approach Rahim but back up as Rahim walks toward them in the parking lot. The officers draw their firearms, and Rahim, who is mostly obscured by a light pole during the altercation, falls to the ground.
It is not clear from the video what specifically led officers to draw their weapons or which officers discharged them. Police have said two officers - an FBI agent and a police officer - fired three shots. Officials released the original version of the video, which comes from a nearby Burger King restaurant, as well as a version that zooms in on the encounter.
Police Commissioner William Evans said Monday that the video "speaks for itself," showing that Rahim, who is black and Muslim, was fatally shot after refusing to drop a military-style knife and that officers were backing away when they fired their guns.
"This guy had a malicious intent," Evans said. "We averted a serious tragedy that day."
Rahim's family said in a statement that the blurry video shows that the 26-year-old security guard was not the initial aggressor and that he did not appear to be breaking any laws as he walked toward a bus stop on his way to work on June 2.
They suggested many unanswered questions remain, including whether deadly force was necessary and whether the decision to approach Rahim with a team of armed police officers "in a military-like formation, without benefit of a warrant, constituted an attempted illegal arrest."
"The family asks that the public keep an open mind," the statement said. "The video reveals part of the story, but not the entire story."
Suffolk District Attorney Daniel Conley said release of the video before his office's investigation into the incident is complete comes as the public has demanded greater "transparency and accountability" when officers use lethal force. Media and technology, he said, have also made it easier for "rumor, speculation, and inaccurate information" to spread.
"For this reason, we've agreed to release certain video evidence earlier when it can help illuminate the facts, and when doing so won't compromise the integrity of the investigation," he said.
Authorities last week showed the video to black and Muslim community leaders and Rahim's family and had promised to release the video publicly after Rahim's burial, which was Friday.
Darnell Williams, president of the Urban League of Eastern Massachusetts, said the video largely corroborated the police account of the shooting. But Abdullah Faaruuq, an imam at the Mosque for the Praising of Allah in Boston, suggested it was "inconclusive" because it's not clear if Rahim had a knife in his hand.
Ibrahim Rahim, who had been an imam at a Boston mosque before leaving to lead one in Oakland, California, also suggested in the hours after the shooting that his brother had been shot in the back while talking to his father on his cellphone.
But the family, after viewing the video, recanted those statements, which had been posted on social media. They said those comments were based on erroneous third-hand information.
A lawyer for Rahim's family did not immediately respond to a request for comment Monday.
Vincent Lisi, special agent in charge of the FBI's Boston office, said members of the FBI and Boston police's Joint Terrorism Task Force attempted to question Rahim after they intercepted a message suggesting Rahim planned to carry out an attack on police officers.
Authorities have said the terrorism task force had Rahim under 24-hour surveillance and had intercepted conversations between Rahim and his nephew, David Wright, who was arrested last week on a charge of conspiracy with intent to obstruct a federal investigation. It isn't clear whether Wright has an attorney.
Rahim planned to carry out an Islamic State of Iraq and Syria (ISIS)-style beheading, possibly of controversial conservative activist and outspoken Islam critic Pamela Geller, CBS News correspondent Jeff Pegues reported.
"I'm the number one target for ISIS right now," Geller told CBS News.
On May 3, Geller organized the Prophet Muhammad cartoon drawing contest in Garland, Texas, where police fatally shot two men who opened fire outside the event. Geller told CBS News she has increased her security but has yet to discuss the threat with the FBI.
"It won't end with me or the cops," she said. " ... The one thing that's came out of Garland is ISIS is here. Islamic terrorism is here on the home soil on a weekly, sometimes a daily basis."
Law enforcement sources are still unclear how serious the plot against Geller was and how much of it was just talk.