Adam Smolcic believes a police officer erased a video recording of a fatal police shooting from his cellphone. (CBC)

Vancouver police have identified the man who was fatally shot by an officer on Friday in downtown Vancouver as 58-year-old Michael Vann Hubbard.

An autopsy found that Hubbard, of no fixed address, was killed by a single gunshot.

Police said they are reviewing surveillance video of the shooting obtained from two separate sources.

However, a man who said he used his cellphone to record video of the shooting said he believes a police officer on the scene erased his video.

Adam Smolcic, 25, said he plans to take his phone to a forensics expert to determine whether the video can be retrieved.

"It's like a computer. Everything you delete isn't actually deleted. It's just fragmented on your hard drive," Smolcic told CBC News on Monday.

"They are going to have to go into the internal memory and try and piece it together."

'He was very shaky, but he wasn't making any moves toward the police at all that I saw.'— Adam Smolcic

Hubbard was a suspect in the break-in of a van parked at the 700 block of Granville Street, Vancouver police spokeswoman Const. Jana McGuinness said Friday.

A Vancouver police officer shot and killed the man after he refused to drop an X-Acto utility knife and advanced on police, said McGuinness.

Suspect was not advancing: witness

Smolcic said he was across the street when he saw Hubbard slowly pull a knife from his backpack, and then one of the two officers on the scene pulled out their gun and shot the man.

Smolcic said he did not see Hubbard advance toward the officer before he was shot.

"No, absolutely not. He was very shaky, but he wasn't making any moves toward the police at all that I saw," he told CBC News.

Michael Vann Hubbard, 58, was shot and killed by a police officer in downtown Vancouver on Friday morning. (CBC)

Smolcic said he continued to film the incident after Hubbard was shot, until he was approached by an officer.

"He saw me filming and he came up to me and he asked to see my cellphone. He had my cellphone for a few minutes, and it appeared as though he was previewing the film. He gave me back my cellphone, probably about four or five minutes after he took it, told me to get lost, and of course, I did."

Smolcic, a marijuana activist who prints T-shirts for a living, said there was no video on his phone when he got it back.

Defence lawyer Mark Jette told CBC News police can't seize a phone, or anything else, unless they believe there is material evidence that could be used in a criminal case.

"Police would probably be within their rights to attempt to preserve that evidence. But that means seize and preserve it. Obviously their duty, the police duty at that point, is to make sure the evidence remains secure, and in its original form," said Jette.