Actor Cory Monteith died due to an overdose of a mix of heroin and alcohol, reports dailymail.co.uk.
Monteith's autopsy report was revealed Tuesday.
The actor, best known for his role in musical comedy Glee, was found dead in a Vancouver hotel room July 13. He was 31.
British Columbia Coroners Service officials are still investigating the case further and have only revealed the reason as mixed drug toxicity, involving heroin and alcohol.
The police officials say there was sign of drug overdose in his hotel room.
"There was evidence in the room that was consistent of a drug overdose. It was the opinion of the investigators that it was a drug overdose, but we didn’t want to speculate," police constable Brian Montague said.