The sudden death of "Glee" actor Cory Monteith has sent shockwaves throughout Canada and Hollywood after the rising star’s body was discovered in a downtown Vancouver hotel on Saturday.

Monteith was found dead in his 21st floor room at the Fairmont Pacific Rim Hotel around noon after he failed to check out from his room as scheduled, Vancouver police say.

The Calgary-born, Victoria-raised 31-year-old actor was best known for his role as Finn Hudson in the popular TV series "Glee."

“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 this death,” said Acting Chief Doug LePard.

Police said there was no indication of foul play in Monteith’s death.

“There were others with Mr. Monteith in the room, but video and fob key entries show him returning to his room alone and we believe he was alone when he died,” LePard said.

Police would not answer questions about any evidence of drug use.

A troubled past

Monteith has been candid with the media about his troubled childhood in Victoria, saying he was an “at-risk youth,” who dropped out of high school and started drinking and doing drugs.

The actor has said the experience is what spurred his involvement with youth-focused charities including Project Limelight, a free theatre program for children living in Vancouver’s troubled Downtown Eastside.

But his personal problems resurfaced after he struck it big with his role in “Glee.” Monteith voluntarily checked himself into rehab in April for substance addiction.

The Coroner’s Service said his cause of death was not immediately apparent and an autopsy will be performed.

“The death of a young person is a tragedy for their family, friends and community,” said Chief coroner Lisa Lapointe. “A sudden death is more shocking and our hearts go out to the family and friends who are mourning the loss of this young man.”

Monteith’s family spoke in a press release saying they are in shock and mourning the tragic loss.

His co-star and girlfriend Lea Michele, who plays Finn's on-screen girlfriend in "Glee," also issued a brief statement, requesting privacy.

Outpouring of grief

Meanwhile, tributes from around the world were pouring in on social media Sunday as those who admire the actor learned of his sudden death.

Many of those sentiments came from Vancouver, where Monteith once lived and worked, getting his start in the entertainment world.

“Sad to hear about Cory Monteith. Met him last year. Well-spoken, caring, funny man. Thoughts are with his family + friends,” Vancouver Mayor Gregor Robertson tweeted.

Little Sister's, a book and art store on Davie Street, remembered Monteith from visiting the establishment before his "Glee" days.

“RIP Corey Monteith. Our condolences to friends and family. Monteith lived just around the corner from the store at the time he got the part of Finn on 'Glee' and would pop in when he was back in town. We'll miss your visits, Corey,” a post on the business’ Facebook page reads.

"When I first saw 'Glee,' I was ecstatic for Cory. A local boy and a great guy. My thoughts to his family and friends. He will be remembered," wrote Vancouver actor Osric Chau.

The executive producers of "Glee" and Fox also issued a statement on Saturday night, saying, "We are deeply saddened by this tragic news. Cory was an exceptional talent 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."

Emotional fans left flowers, letters and stuffed animals outside of the hotel Monteith’s body was found at to commemorate his death Sunday.

A man who said he is Monteith's cousin was visibly upset, laying down flowers at a small memorial set up outside the hotel.

"He's my cousin...but I wouldn't like to talk right now. A little more time, please," he told reporters.

A card attached to one of the bouquets left at the vigil read “Only the good die young. You did us proud,” and included the hashtags #ripcory and #prayforlea.

With files from The Canadian Press