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.
Hoffman - no matinee-idol figure with his tubby, lumpy build and limp blond hair - made his career mostly as a character actor, and was one of the most prolific in the business.
The stage-trained actor's rumpled naturalism made him one of the most admired performers of his generation. He was nominated for Academy Awards four times in all.
Hoffman 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 and developing a heroin problem that led to a stint at a rehabilitation facility.
The law enforcement officials said Hoffman's body was discovered in a bathroom by a friend who made the 911 call and his assistant.
His family called the news of Hoffman's death "tragic and sudden.
""We are devastated by the loss of our beloved Phil and appreciate the outpouring of love and support we have received from everyone," Hoffman's family said in a statement.
In one of his earliest roles, he played a spoiled prep school student in "Scent of a Woman" in 1992. One of his breakthrough roles came as a gay member of a porno film crew in "Boogie Nights," one of several movies directed by Paul Thomas Anderson that he would eventually appear in.
He often played comic, slightly off-kilter characters in movies like "Along Came Polly," ''The Big Lebowski" and "Almost Famous."
More recently, he was Plutarch Heavensbee in "The Hunger Games: Catching Fire" and was reprising that role in the two-part sequel, "The Hunger Games: Mockingjay," which is in the works. And in "Moneyball," he played Art Howe, the grumpy manager of the Oakland Athletics who resisted new thinking about baseball talent.
Just weeks ago, Showtime announced Hoffman would star in "Happyish," a new comedy series about a middle-aged man's pursuit of happiness.
In "The Master," he was nominated for the 2013 Academy Award for best supporting actor for his role as the charismatic leader of a religious movement. The film, partly inspired by the life of Scientology founder L. Ron Hubbard, reunited the actor with Anderson.
He also received a 2009 supporting nomination for "Doubt," as a priest who comes under suspicion because of his relationship with a boy, and a best supporting actor nomination for "Charlie Wilson's War," as a CIA officer.
Born in 1967 in Fairport, N.Y., Hoffman was interested in acting from an early age, mesmerized at 12 by a local production of Arthur Miller's "All My Sons." He studied theater as a teenager with the New York State Summer School of the Arts and the Circle in the Square Theatre. He then majored in drama at New York University.
In his Oscar acceptance speech for "Capote," he thanked his mother for raising him and and his three siblings alone, and for taking him to his first play. Hoffman's parents divorced when he was 9.
With a versatility and discipline more common among British performers than Americans, he could seemingly take on any role, large or small, loathsome or sympathetic.
On Broadway, he took on ambitious roles like Willy Loman in "Death of a Salesman," Jamie in "Long Day's Journey Into Night" and both leads in "True West." All three performances were Tony nominated.
His 2012 performance in "Death of a Salesman" was praised as "heartbreaking" by AP theater critic Mark Kennedy.
"Hoffman is only 44, but he nevertheless sags in his brokenness like a man closer to retirement age, lugging about his sample cases filled with his self-denial and disillusionment," Kennedy wrote. "His fraying connection to reality is pronounced in this production, with Hoffman quick to anger and a hard edge emerging from his babbling."
Two films starring Hoffman premiered last month at the Sundance Film Festival: the espionage thriller "A Most Wanted Man," directed by Anton Corbijn, and "God's Pocket," the directorial debut of John Slattery.
Hoffman is survived by his partner of 15 years, Mimi O'Donnell, and their three children.
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