A man killed in a police-involved shooting at a Nanaimo ferry terminal earlier this year shot himself in the head as police fired their guns at him, a new report from B.C.'s police watchdog says.

The Independent Investigations Office also found that officers involved in the May 8, 2018 incident had reasonable grounds to use lethal force on the man.

According to the report, the man was driving a car stolen in a violent theft in Penticton when he disembarked from the ferry at Departure Bay.

Responding to a tip from ferry staff, officers moved to intercept the man at the terminal – separating him from other ferry traffic and forcing him to stop.

"Once stopped, the evidence is clear that [the suspect], while surrounded by police, raised his gun and shot himself in the head. That was his only intention," said the report. "However, as he did this, the gun would have been pointed a several police officers."

It goes on to say it would have been impossible to tell whether or not the suspect intended shoot at the officers, and that they had to act quickly to protect themselves and the public by opening fire.

The weapon the suspect shot himself with was a .22 calibre pistol with a silencer welded on to it, according to the IIO.

In all, he suffered the self-sustained gunshot wound to the head, and three shots to his abdomen, a shot to his collarbone and another to his left bicep from police.

Paramedics tried to keep him alive with ventilation, but he was losing too much blood within minutes after being shot, the report says. He was then transferred to Nanaimo Regional Hospital and pronounced dead 20 to 30 minutes after being shot.

The report also paints a picture of a man with "several significant recent life challenges," including an injury that prevented him from working and a serious substance addiction. Additional toxicological testing determined the man had enough fentanyl in his system that it was in the lethal range.

The report says it was later confirmed that before his death, the suspect was involved in a shooting that led him to believe he had killed someone. In reality, the person shot did not die as a result of the shooting.

"His conversations with persons known to him demonstrated he was feeling very desperate about his life," it said.

The man has not been identified by police.