The cause of "Glee" actor Cory Monteith's death remained unclear Monday, and authorities in Canada said it could take several days before toxicology test results are in.
Vancouver police Sgt. Randy Fincham said there's nothing to indicate the death was due to illicit drug use.
Monteith, 31, was found dead in his Vancouver, British Columbia, hotel room on Saturday, according to police, who have ruled out foul play.
Police said Monteith had been out with people earlier, but video and electronic records from the hotel indicated he returned to his room by himself early Saturday. He was believed to be alone when he died.
Monteith's passing recalls the lives of Heath Ledger, Corey Haim and River Phoenix — actors who battled substance abuse and died in their 20s and 30s. Monteith talked bluntly about struggling with addiction since he was a teenager, calling it a serious problem and telling Parade magazine in 2011 he was "lucky to be alive."
Monteith admitted himself to a treatment facility in April for substance addiction and asked for privacy as he took steps toward recovery, a representative said at the time. Lea Michele, Monteith's "Glee" co-star and real-life girlfriend, told People magazine that she loved and supported him and was proud he was seeking help. It was not Monteith's first time in rehab. He also received treatment when he was 19.
Michele was asking that everyone respect her privacy "during this devastating time," said her representative, Molly Kawachi of ID-PR.
The Fox network and the producers of "Glee," including 20th Century Fox Television, called Monteith an exceptional performer "and an even more exceptional person." Michele asked for privacy upon hearing the news of his death.
Monteith had recently shot a Canadian film called "All the Wrong Reasons," with actors Kevin Zegers, Karine Vanasse and Emily Hampshire, slated to debut on the festival circuit this fall.
Gia Milani, who produced, directed and wrote the screenplay, said Monteith portrays a ruthless department store manager who shows a unique vulnerability when he helps his wife deal with post-traumatic stress disorder. She said Monteith connected with the role because he had retail experience, working in a Walmart in Vancouver when he was younger.
"There were some risque moments in the film and he's very intense in it and passionate," Gilani told Canadian Press in a telephone interview from just north of Shediac, New Brunswick, her voice still shaky from the shock of Monteith's death over the weekend. "He pulled it off flawlessly."
Milani said Monteith "seemed healthy" when she last saw him four weeks ago in Los Angeles to screen the film for him.
"He looked super fit and he was energetic and excited. He was really good," she said.
She said Monteith showed no signs of a substance abuse problem while shooting the film a year ago in Halifax, Nova Scotia. He was shooting "Glee" at the same time and would take a red-eye flight from Los Angeles to Halifax on Sundays, arrive-mid-morning and "still know his lines and still be fresh and focused," she said.
"He had amazing ideas and he brought a lot to the role," said Milani. "He had just an outstanding work ethic."
Milani said Monteith told her "he felt like he had achieved so much with 'Glee' that it gave him permission to do other things," including smaller films such as hers.
Off the set, Monteith was "always gracious" in accommodating fans when they approached him as he dined in restaurants, said Milani.
"Never one time was he rude, never one time did he say no," she said. "He was a super accessible guy, which is just all the more painful."
Outside the Vancouver hotel, Monteith's fans created a makeshift memorial.. #RipCoryMonteith and #StayStrongLea became trending topics on Twitter.
In England, what was supposed to be a weekend celebration of "Glee" turned into an impromptu memorial after news of Monteith's death rocked a fan convention.
"The news was devastating. No one had any idea what to say or do," said Chloe Harvey, an 18-year-old fan from Portsmouth, England. "It just shows how much of a truly amazing guy Cory was that everyone was so shocked and emotional about the news."
"Glee," with its catchy song-and-dance numbers and high-profile guest stars like Gwyneth Paltrow and Britney Spears, became an instant hit when it debuted in 2009 and made celebrities of Montieth and the rest of the relatively unknown cast.
Monteith served as the show's resident hunk with a heart of gold. He played Finn Hudson, a football quarterback with two left feet who found more camaraderie in the choir room than on the football field. After his character graduated high school, Hudson sought out to find himself before settling on what he wanted to do with his life: become a teacher and mentor.
In real life, Monteith was an avid supporter of an arts mentoring program, Project Limelight, which worked with young people in Vancouver's poverty-stricken Downtown Eastside district. In May 2012, Monteith and Richard Branson, the Virgin Group founder and chairman, traveled to Vancouver to support the charity.
"Cory Monteith was a beautiful soul," Branson said in a blog post on Virgin's website. "His awareness of his own struggles led him to reach out to young people all over the world with deep compassion and empathy to help them through their struggles."
"We'll never forget watching him on the streets in Canada," wrote Branson. "Cory wanted other youth to have the chance to discover their strengths and potential through the arts."
AP writer Charles J. Gans in New York contributed to this report.
Follow AP Entertainment Writer Derrik J. Lang on Twitter at http://www.twitter.com/derrikjlang .