The British Columbia Coroner's Service said that "Glee" star Cory Monteith, 31, whose body was found in a Vancouver hotel room on Saturday, died of a heroin and alcohol overdose.
Monteith's body was discovered by staff just after noon at the Fairmont Pacific Rim Hotel, Vancouver police confirmed at a news conference Saturday night.
The coroner's office determined the cause of death to be "a mixed-drug toxicity involving heroin and alcohol," according to a statement. Foul play was not suspected.
"On behalf of the Vancouver Police, I want to pass on our condolences to the family, friends, castmates and millions of fans of Mr. Monteith," acting chief Doug LePard said.
"As was the case in countless homes, I watched 'Glee' regularly with my daughters, and I know there will be shock and sadness in many households with the news of his tragic death."
Monteith's "Glee" character Finn Hudson made singing cool again.
The heartthrob Finn was a popular football star who didn't want to join the school's glee club at first but quickly became the glue that held the group together.
The six-foot-three actor lent his voice to show stopping versions of U2's "One" and Michael Jackson's "Man in the Mirror."
Recently, Monteith's Finn had graduated from the high school but returned to coach the glee squad.
Off set, the actor was dating his "Glee" co-star Lea Michele.
Monteith played a popular and outgoing character on the show but, according to the New York Times, the actor struggled with substance abuse in his personal life.
He recently voluntarily checked himself into a treatment center for an unspecified substance addiction.
Monteith also previously sought treatment when he was 19.
The Canadian actor said in a 2011 interview that he hoped that his struggles with addiction would offer an example to others.
"I don’t want kids to think it's O.K. to drop out of school and get high, and they’ll be famous actors, too," he said.
"But for those people who might give up: Get real about what you want and go after it."