Story highlights Lea Michele is grieving alongside Monteith's family, her reps say

Death was nothing more "than a most-tragic accident," coroner says

Monteith was found dead Saturday in a Vancouver hotel room

The actor, 31, had been on the hit Fox series since it premiered in 2009

"Glee" star Cory Monteith died as a result of "a mixed drug toxicity, involving heroin and alcohol," the British Columbia Coroners Service said Tuesday.

"At this point there is no evidence to suggest Mr. Monteith's death was anything other than a most-tragic accident," the coroners service said in a statement, adding that no further details were available pending a full investigation.

Monteith, 31, was found dead Saturday in his room by staff members at Vancouver's Fairmont Pacific Rim Hotel after he missed his checkout time.

The actor spent time in rehab this year, checking into a drug addiction treatment facility in late March.

Monteith had been frank about his struggles with substance abuse, telling Parade magazine in 2011 that he began using drugs at 13 and by 19 went into rehab after his mother and friends intervened.

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Photos: Photos: TV shows that have lost stars Photos: Photos: TV shows that have lost stars TV shows that have lost stars – The death of actor Cory Monteith at the age of 31 meant his hit show "Glee" had to figure out how best to deal with his character. Monteith's character, Finn Hudson, also died on the series. "Glee" is not the only one to face such a challenge... Hide Caption 1 of 14 Photos: Photos: TV shows that have lost stars TV shows that have lost stars – The producers of the rebooted "Dallas" revisited the "Who shot J.R." mystery of the original show following Larry Hagman's death, of complications from cancer, in 2012. Hide Caption 2 of 14 Photos: Photos: TV shows that have lost stars TV shows that have lost stars – John Spencer was beloved as Leo McGarry on NBC's "The West Wing." His death by heart attack in 2005 was written into the show. Hide Caption 3 of 14 Photos: Photos: TV shows that have lost stars TV shows that have lost stars – During his 12 years on "Law & Order," Jerry Orbach (left) starred as Detective Lennie Briscoe, and was partnered with a few actors, including Chris Noth as Detective Mike Logan. His character had retired from the force when he joined the spin-off "Law & Order: Trial By Jury," where Briscoe was written out of the show after Orbach's death in 2004 from prostate cancer. Hide Caption 4 of 14 Photos: Photos: TV shows that have lost stars TV shows that have lost stars – John Ritter, center -- shown here with "8 Simple Rules" cast mates (from left) Katey Sagal, Amy Davidson, Kaley Cuoco, Billy Aaron Brown and Martin Spanjers -- died of an aortic dissection at the height of the show in 2003. His character also died on the show and two additional cast members, David Spade and James Garner, were cast after a hiatus. Hide Caption 5 of 14 Photos: Photos: TV shows that have lost stars TV shows that have lost stars – Nancy Marchand won over critics and fans alike as Tony's cantankerous mother Livia Soprano. When the actress, shown here with "Sopranos" co-star Dominic Chianese, died from emphysema and lung cancer in 2000, her character's death also was written into the script. Hide Caption 6 of 14 Photos: Photos: TV shows that have lost stars TV shows that have lost stars – The "NewsRadio" cast, (from left), Khandi Alexander, Andy Dick, Stephen Root, Phil Hartman, Dave Foley, Maura Tierney, Joe Rogan and Vicki Lewis were pretty tight prior to Hartman's death. Hartman, who was shot to death by his wife in 1998, was revealed to have died of a heart attack at the beginning of the fifth season, and Hartman was replaced by actor Jon Lovitz. Hide Caption 7 of 14 Photos: Photos: TV shows that have lost stars TV shows that have lost stars – It was during rehearsals for the series "The Royal Family" that Redd Foxx died of a heart attack in 1991. The show had been intended as a comeback vehicle for Foxx and did not survive long after his death. Hide Caption 8 of 14 Photos: Photos: TV shows that have lost stars TV shows that have lost stars – Nicholas Colasanto (on the left) is seen here with his "Cheers" co-stars Rhea Perlman, Ted Danson and Shelley Long. His character of Coach Ernie Pantusso was written out of the show as having also died when the actor succumbed to a heart attack in 1985. Hide Caption 9 of 14 Photos: Photos: TV shows that have lost stars TV shows that have lost stars – The very handsome Jon-Erik Hexum was just 26 in 1984 when he shot himself with a prop gun on the set of his new show, "Cover Up." The blank from the gun drove a piece of his skull into his brain and he was taken off of life support a week later. His character was killed off the show. Hide Caption 10 of 14 Photos: Photos: TV shows that have lost stars TV shows that have lost stars – When actor Michael Conrad died of cancer in 1983, his "Hill Street Blues" character, Sgt. Phil Esterhaus, also died. Hide Caption 11 of 14 Photos: Photos: TV shows that have lost stars TV shows that have lost stars – When "Dallas" actor Jim Davis died of cancer in 1981, his character Jock Ewing also died on the show. Here he is seen with his co-star, Barbara Bel Geddes, who played Eleanor Southworth "Miss Ellie" Ewing. Hide Caption 12 of 14 Photos: Photos: TV shows that have lost stars TV shows that have lost stars – Jack Soo was one of the original cast members of the hit show "Barney Miller." The series commemorated him in a special episode featuring flashbacks of his character after Soo died of cancer in 1979. Hide Caption 13 of 14 Photos: Photos: TV shows that have lost stars TV shows that have lost stars – Diana Hyland only appeared in four episodes as the mother on "Eight is Enough" before her death from cancer in 1977. Dick Van Patten played her TV husband, and his character became a widower who fell in love and remarried when a new actress was cast. Hide Caption 14 of 14

Monteith had been on Fox's hit musical comedy show since it began in 2009, playing the dim quarterback of the football team who is forced to join the glee club. After graduation, he comes back to town and helps direct a musical at the school.

Adam Shankman, who directed an episode for each of the past three seasons, told CNN's Poppy Harlow that he had talked to Monteith on Saturday morning. The actor said he wanted to come down to California to Jet Ski.

Shankman described Monteith as the glue of "Glee." He was always welcoming, whether it was to a guest director or a new cast member, Shankman said.

The actor knew all of his lines when filming began each time and would congratulate his fellow cast members when he thought they did well.

"He showed up every day, and he was a delight," Shankman said.

Offscreen, Monteith was dating co-star and on-screen love interest Lea Michele.

He was madly in love with her, Shankman said. "He felt like it had renewed his spirit."

Representatives for Michele issued a brief statement Monday saying the actress is "deeply grateful for all the love and support she has 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."