SEATTLE (AP) — A sheriff’s deputy who responded to a call about a robbery suspect at a Washington state home mistakenly shot and killed the homeowner — an off-duty police officer who was trying to detain the man.

Authorities in Clark County say the suspect fled in a stolen Mercedes after robbing a gas station in Vancouver, near Portland, Oregon, at gunpoint Saturday night. He eluded police on a busy highway and ran off after they stopped his vehicle with spike strips.

The man wound up about 10 miles away at the Battle Ground home of 52-year-old Vancouver police Officer Donald Sahota, where he pounded on the door, said he’d been in a car crash and asked for help. Nothing in an account released by investigators late Sunday suggested the officer and suspect knew each other.

Because the man matched the description of the suspect, Sahota went outside to detain him while his wife called 911, according to the account from the Lower Columbia Major Crimes Team, the regional investigative team reviewing the shooting.

The suspect began fighting with Sahota, stabbed him repeatedly with an unknown object, and then broke free and ran toward Sahota’s house.

Sahota had lost hold of his gun during the struggle but regained it and chased after the suspect just as a deputy arrived and shot the off-duty officer with a rifle.

Sahota collapsed on his front porch before responding officers figured out he wasn’t the suspect. The suspect surrendered to police moments later.

Sahota’s wife had reported to dispatchers that her husband was an armed, off-duty officer who was outside confronting the suspect, investigators said.

“My heart goes out to Officer Sahota’s family and friends and those of us in his VPD family as well,” Vancouver Police Chief James McElvain said in a statement. “His death is a tragic loss, and he will be deeply missed by many.”

The suspect, identified as Julio Cesar Segura, 20, appeared Monday in Clark County Superior Court after being arrested for investigation of attempted first-degree murder, robbery and other charges. Judge John Fairgrieve set bail at $5 million, saying it was “hard to think of a more dangerous series of acts,” The Columbian newspaper reported.

Sahota joined the department in April 2014 after stints with the Gresham and Port of Portland police departments in Oregon.

In Vancouver, his assignments included patrol, being an armorer and most recently the training unit. He also leaves behind two children, Vancouver police said.