The Oscar winner was 46.
Academy Award-winning actor Philip Seymour Hoffman was found dead Sunday in his Greenwich Village apartment with what law enforcement officials said was a syringe in his arm. He was 46.
The two officials told The Associated Press that glassine envelopes containing what was believed to be heroin were also found with Hoffman. Those items are being tested.
The law enforcement officials, who spoke to The Associated Press on condition of anonymity because they are not authorized to speak about evidence found at the scene, said the cause of death was believed to be a drug overdose.
In late May, Hoffman finished a 10-day stint in a rehab program for a drug problem that included snorting heroin.
He spoke candidly over the years about past struggles with drug addiction. After 23 years sober, he admitted in interviews last year to falling off the wagon.
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Hoffman has three children — Cooper, 10, Tallulah 7, and Willa, 5 — with costume designer Mimi O'Donnell.
The family released a statement via Hoffman's publicist, Karen Samfilippo:
"We are devastated by the loss of our beloved Phil and appreciate the outpouring of love and support we have received from everyone. This is a tragic and sudden loss and we ask that you respect our privacy during this time of grieving. Please keep Phil in your thoughts and prayers."
Hoffman won the best-actor Oscar for Capote in 2006. He was nominated for supporting-actor Oscars for his roles in The Master, Doubt and Charlie Wilson's War.
He most recently starred as Plutarch Heavensbee in the summer blockbuster The Hunger Games: Catching Fire. He will reprise the role in The Hunger Games: Mockingjay, Part I, set for a November release. The Hunger Games: Mockingjay, Part II is currently filming.
"He's one of the best actors on the planet," Catching Fire director Francis Lawrence told USA TODAY in November. "I thought he would be great at it. I just wasn't sure he'd want to do (the film). But he did."
Hoffman had recently attended the Sundance Film Festival where he was debuting two films: God's Pocket and A Most Wanted Man.
Hoffman received wide acclaim for his stage work, as well.
On Broadway, he earned Tony nominations acting in revivals of the classics True West, Long Day's Journey Into Night and Death of A Salesman. Salesman teamed him with director Mike Nichols, with whom Hoffman had worked earlier in an acclaimed Public Theater Shakespeare in the Park staging of The Seagull, alongside Meryl Streep and Natalie Portman.
Nichols released this statement on the actor's passing: "No words for this. He was too great and we're too shattered."
Hoffman was a member of New York's Labyrinth Theater Company, whose other members include Ethan Hawke, Bobby Cannavale and acclaimed playwright Stephen Adly Guirgis. Hoffman also worked as a director, earning Drama Desk Award nominations for his direction of Guirgis' Jesus Hopped the 'A' Train and Our Lady of 121st Street.
He also was recognized for his television work, receiving a nomination for his performance in the 2005 miniseries Empire Falls on HBO. He was set to return to cable in a comedy about an unhappy adman called Happyish for Showtime. On Sunday, the network said that only the pilot had been completed.
In 2005, Hoffman spoke to USA TODAY about his role in Capote: "I began to see that this wasn't simply an odd man, an odd writer. What he discovered writing In Cold Blood embodies what a lot of people go through. He struggled with who he was. He struggled with finding his place in the world. I think he struggled with how much attention he wanted to cast on himself."
On fan support, he said: "I don't want compliments. I want to know what I'm doing right or doing wrong. No one wants to hear they suck. But sometimes it's the best thing you can hear. It's the only way you're really going to get better."
Contributing: The Associated Press, Elysa Gardner, Gary Levin