Heroin found in Philip Seymour Hoffman's apartment

The sudden death of the 46-year-old father of three young children, hailed by many as the finest character actor of his generation, has shocked Hollywood and devastated his family.

Police said he was found on the bathroom floor in his Manhattan apartment, a syringe in his arm, wearing shorts and a T-shirt.

According to US media at least 50 envelopes of heroin littered the $10,000 a month apartment in plush Greenwich Village, but there has been no official confirmation of the amount of drugs.

"Preliminary tests have indicated that the drugs were heroin," a law enforcement official told AFP, without confirming the quantity found.

Hoffman was last seen on Saturday and the alarm was reportedly raised by his estranged girlfriend Mimi O'Donnell when he failed to show at a playground to see his children on Sunday.

She was also quoted by US media as saying he was high when she last saw him on Saturday afternoon and spoke to him that evening.

Police say his death seems to have been the result of an overdose but refused to release further details.

New York pathologists have begun the autopsy, but a spokeswoman for the New York City chief medical examiner's office said no further update was expected on Monday.

In a career spanning more than 20 years and 50 films, Hoffman mesmerized filmgoers with his portrayal of some of the most repellent and yet electrifying characters of the silver screen.

He won a best actor Oscar for his performance as Truman Capote in the 2005 film "Capote" and was nominated for three further Academy Awards as a supporting actor in 2008, 2009 and 2013.

Broadway announced that it would dim its lights for one minute at 7:45 pm on Wednesday in memory of the celebrated actor.

Charlotte St Martin, executive director of the Broadway League, described Hoffman as a "true artist who loved theater.

But for all his talent, Hoffman struggled with addiction.

Celebrity website TMZ reported that Hoffman admitted in May to falling off the wagon more than a year previously, after two decades of sobriety, starting with prescription pills and escalating to snorting heroin.

At the time he said the heroin binge had "lasted a week or so" and that he checked himself into a rehab center for 10 days, crediting "a great group of friends and family" for helping him.

But in August he dropped out of shooting the spy thriller "Child 44" for "undisclosed reasons," sparking rumors about his health.

The last time he was seen at an official event was at the Sundance Film Festival in the US state of Utah in mid-January, where some witnesses described him as pale and disheveled.

'Tragic and sudden loss'

Since his death, it has emerged that he was recently living apart from O'Donnell and their children. The rented apartment in Greenwich Village where he died was close to the family home.

Talking about his addiction to drugs and alcohol, he told the CBS show "60 minutes" in 2006: "I was 22 and I got panicked in my life."

His family has released a brief statement asking for privacy to mourn their "tragic and sudden loss."

Tributes have poured in from fellow actors -- as well as from the US Secretary of State.

"Hard to believe Philip Seymour Hoffman's gone," the top US diplomat John Kerry tweeted, calling him an "incredible actor (who) really became Capote."

"He was a giant talent," said Tom Hanks, who starred with Hoffman in "Charlie Wilson's War."