Cory Monteith died of mixed drug toxicity involving heroin and alcohol, the British Columbia Coroners Service said today.

"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," coroner Barb McLintock wrote in a bulletin. "The investigation into this death by the BC Coroners Service is continuing, and no other details are available at this time. ... When the investigation is concluded, a coroners report will be issued."

Monteith, 31, was found dead in his room at the Fairmont Pacific Rim Hotel in Vancouver on Saturday afternoon after he failed to check out on time.

McLintock added that his family has been notified about the cause of death, and has asked for privacy "at this difficult time."

"We are so saddened to confirm that the reports on the death of Cory Monteith are accurate," his rep told ABC News in a statement at the time of his death. "We are in shock and mourning this tragic loss."

The "Glee" star had a history of substance abuse. In 2011, he told Parade magazine that, at 19, he went to rehab, saying that he took "anything and everything" and was "lucky to be alive." This past April, his rep confirmed that he entered treatment once again for addiction.

His girlfriend of more than a year, "Glee" co-star Lea Michele, 26, stood by him.

"I love and support Cory," she said at the time. "I am grateful and proud he made this decision."

Since his death, there has been outpouring of support from celebrities, especially his "Glee" cast mates. But Michele has been mourning privately with his family, her rep told ABC News in a statement Tuesday.

"Lea is deeply grateful for all the love and support she's received from family, friends, and fans. Since Cory's passing, Lea has been grieving alongside his family and making appropriate arrangements with them," the statement said. "They are supporting each other as they endure this profound loss together. We continue to ask the media to respect the privacy of Lea and Cory's family."