VANCOUVER - Vancouver's police chief says officers canvassed witnesses after one of their own shot and killed a mentally ill man five years ago but did not come across the video that has prompted another review of the case.

Chief Jim Chu apologized three times Thursday during a news conference to the family of Paul Boyd, who died in a hail of bullets on Aug. 14, 2007 after police responded to several 911 calls.

Chu said he also called Boyd's family to say sorry for their loss, but the man's sister, Deborah Boyd, said the chief's apologies ring hollow and are nothing more than excuses for an officer who should have been disciplined for his actions.

"They never have taken responsibility for it," Boyd said. "The public would respect them so much more if they would admit when they make a mistake and try to rectify it.

"Anyone who's seen that video can see that an unarmed man was shot, in cold blood basically," she said. "There's been so many investigations and there's been no recourse for anyone. Everybody's got their job and there's been no disciplinary action at all."

Chu told a news conference that 12 witnesses were located and were interviewed but police did not know someone had videotaped the last moments of Paul Boyd's life.

A final report submitted to the Crown listed more than 100 witnesses to the police-involved shooting in an upscale shopping area but even then, the force was unaware of the video until it was released to the media this week, Chu said.

"I do not know why that evidence was not uncovered that night. We looked for witnesses that night, many were located. We also did a search and canvass the following day to see if there's store videos or other evidence that could be found that day."

Police also appealed to the public for information, but learned nothing about any video, said Chu, who started his job the day of the fatal shooting.

"The night that it happened, I went to the scene, I looked at the perimeter, the officers canvassing for witnesses, I talked to the investigators that were there that night."

The video, which shows the 39-year-old animator crawling on the street before he was shot dead, was taken by a Winnipeg tourist.

It shows Const. Lee Chipperfield firing eight shots at the bipolar man before the ninth and fatal shot to the head.

The release of the video prompted Attorney General Shirley Bond to have the Alberta Serious Incident Response Team investigate the incident, which has already been reviewed three times.

"I was very disturbed by the video," Chu said. "It was very troubling to see that. I think I share the same emotional reaction that many other police officers experienced when they saw that video."

On Wednesday, the Vancouver Police Department posted a chronology of the night that Boyd died, starting with multiple 911 calls at 9 p.m., his "violent struggle" with four officers and his death at 9:30 p.m.

However, Deborah Boyd said the situation could have been diffused if the first two officers who arrived on the scene had handcuffed her paranoid brother.

"I think it's pretty clear from the video what happened," Boyd said, adding she's hoping justice will still be served for her brother.

A March 2012 report by the Office of the Police Complaint Commission said two plainclothes officers first arrived on the scene after receiving 911 calls about a disturbance. They were followed by two uniformed constables, including Chipperfield.

The report said Boyd was first found by police as he sat on a bench talking to another man and appeared calm.

However, when one of the officers approached Boyd, the officer reported Boyd appeared to be trying to conceal a hammer.

The report said at that point, the officer drew his gun and ordered Boyd on the ground. When an officer approached, trying to handcuff him, "Boyd jumped up, wielding a bike chain and lock" and struck the officer on the side of the head, knocking him to the ground, the report said.

A second officer was also struck by the chain.

The report said Boyd ran into the middle of the street where he continued to swing the chain.

It said when Boyd approached Chipperfield and two others in an aggressive manner, Chipperfield began firing the first of what would be nine shots, with the final one fired into Boyd's head, killing him.

Commissioner Stan Lowe noted that at some point, probably after the fifth shot, Boyd had fallen to the ground and dropped the bike chain and that one of the officers instructed the others to hold their fire while he removed the chain from Boyd's reach.

But Chipperfield continued firing at Boyd, the report said.

Lowe's report noted witness accounts are "unclear" about what position Boyd was in before he was killed.

"Some witnesses describe Mr. Boyd as standing and advancing towards police, while others describe Mr. Boyd as stationary and in a variety of positions," Lowe wrote.

But the new video shows Boyd crawling across the street.

Chipperfield testified at a coroner's inquest that he believed Boyd was still armed when he fired the fatal shot to the man's head.

Chu said Chipperfield currently works in the force's forensics identification unit and no longer responds to 911 calls.

The department now provides mandatory training for patrol officers to deal with mentally ill people, he said, noting the force released a report in 2008 on the health-care system's failure to deal with people who are mentally ill.