Toronto police have released the causes of death of three people at a suburban home in Toronto last Thursday, at least one of which involved a crossbow.

Det. Sgt. Mike Carbone told reporters Monday that a female victim was killed by ligature strangulation, a man died by “crossbow bolt stab wound to the neck” and the other man was killed by a “single arrowhead stab wound to the neck.”

The woman and one of the males were found dead in a garage at the residential property in Scarborough, while the third victim was found on a driveway, Carbone said.

Police had responded to a 911 report of a stabbing, he said.

Brett Ryan, 35, faces three charges of first-degree murder.

Carbone said Ryan and another person were treated in hospital after Thursday’s incident. The other man has been released from hospital.

Asked whether the other individual will face any charges, Carbone said police are still investigating.

“If it’s appropriate to lay some charges in the case of that other individual then we will do so,” he added.

Carbone appealed for witnesses who may have spoken to Ryan in the days before the murders. “Our role is to try and find out what set this off,” he said.

The detective said an apartment on Queen’s Quay near Toronto’s waterfront was “associated” with Ryan. It was searched by the bomb squad Thursday and “items” were found but they “were not of any danger to members of the public,” he added.

In 2008, Ryan was accused of robbing more than a dozen banks in the Toronto area, and nicknamed the “Fake Beard Bandit.” In January 2009, he was convicted on charges related to the bank robberies and served three years and nine months behind bars. Carbone said he is not aware of any police dealings with Ryan since then.

Since his release, Ryan may have been attending a local university, said the detective.

Carbone said he’s looking to speak with anyone who communicated with Ryan, particularly on Aug. 25. He urged possible witnesses to contact Crime Stoppers or call him at 416-808-7400.