Investigators looking into the fatal shooting of a homeless man by Vancouver police are appealing for help from the public, including people who may have witnessed the incident.

The Abbotsford Police Department, which is investigating the March 20 shooting, is releasing video surveillance footage showing the two people in hopes they can be identified and interviewed.

Michael vann Hubbard was shot and killed after two Vancouver police officers approached him because they thought he may have been breaking into vehicles.

It turned out he wasn't involved in any break-ins, but police say vann Hubbard was shot when he walked towards an officer while holding an X-Acto knife.

Abbotsford police are also looking for help in determining vann Hubbard's activities in the days and hours before his death.

Police say they haven't been able to get a statement or the cellphone of a man who claimed he used the phone to film the shooting.

Police have reviewed videos captured from two area cameras. Video footage from one of these cameras shows two witnesses to the event that have not yet been identified or interviewed, police said.

"Our hope is that the distribution of the attached video will enable us to do those things," said Const. Ian MacDonald, a spokesman for the Abbotsford Police Department.

"The background in the video is blurred and only the two witnesses are observable in the clear portion as they walk southbound on Homer Street,'' he said.

The Abbotsford Police Department is also requesting the public's assistance in determining the location and activities of vann Hubbard during the hours and days leading up to the incident on March 20.

Anyone with information about the persons captured on the video, Mr. Vann Hubbard's actions prior to contact with Vancouver police officers on March 20, or any other information about the incident should call the Abbotsford Police Major Crime Unit at 604-859-5225.