The British Columbia Coroner's Office has confirmed that Glee star Cory Monteith passed away due to a toxic mixture of heroin and alcohol. The autopsy was allegedly completed on Monday, but no other details are available at this time since the investigation is still ongoing. "It should be noted that at this point there is no evidence to suggest Mr. Monteith's death was anything other than a most-tragic accident," the report, which was released yesterday afternoon, stated.

Monteith, 31, was found dead on Saturday night in a Vancouver hotel room, where he had been staying for a week. Alcohol and other substances were reportedly found in his hotel room. A source told Radar Online that he spoke to Monteith at a bar the night before his death, and that Monteith did not drink that night. Other sources, however, claim to have seen Monteith drinking, albeit lightly, in the days before his death. The actor was also spotted attending Alcoholics Anonymous meetings during this stay in Vancouver.

Matthew Morrison and Cory Monteith Matthew Morrison performed an emotional tribute to Cory Monteith.

SEE ALSO: Cory Monteith and Lea Michele Reportedly Considering Moving In Together Before His Death

The Glee star entered a 30-day rehab stint for substance abuse issues last April, after nearly a decade of sustained sobriety. In 2011, Monteith told Parade magazine that he began smoking pot and drinking at age 13, and by age 16 was "doing anything and everything, as much as possible." He admitted that he was "lucky to be alive."

Monteith's co-star and girlfriend, Lea Michele, reportedly gave him an ultimatum when he relapsed earlier this year. A source told Us Weekly that she asked Glee creator Ryan Murphy to help stage an intervention for Monteith, where she reportedly told her boyfriend, “Clean up, or I’m out of here.” Michele publicly voiced support for his decision to enter rehab, saying, “I love and support Cory and will stand by him through this. I am grateful and proud he made this decision.”

Cory Monteith Dead Lea Michele Reacts Actors Lea Michele and Cory Monteith of the TV series "Glee" arrive at the 19th annual Screen Actors Guild Awards in Los Angeles, California January 27, 2013.

SEE ALSO: Naya Rivera Heartbroken Over Cory Monteith Death

Monteith’s co-stars on Glee have also publicly commented on his death in the days following the tragedy, with Dot-Marie Jones tweeting that her “heart is broken.” Producers for the show also released a statement hours after his death, saying that "we are deeply saddened by this tragic news. Cory was an exceptional talent and and an even more exceptional person. He was a true joy to work with and we will all miss him tremendously. Our thoughts and prayers are with his family and loved ones."

The upcoming fifth season of Glee is currently being filmed and is still scheduled to premiere on September 18. However, new reports say the season premiere may be pushed to November due to Monteith's passing.

Cory Monteith had worked on a movie called All The Wrong Reasons before his passing, and stills from the film have just been released. He portrayed a store manager called James Ascher, and is seen wearing a smart shirt and tie along with wire-rimmed glasses.