Actor Philip Seymour Hoffman, who won an Academy Award for the film "Capote," was found dead in his New York City apartment on Sunday in what a police source described as an apparent drug overdose.

NEW YORK CITY, NEW YORK, UNITED STATES (FEBRUARY 2, 2014)(REUTERS0 -  Actor Philip Seymour Hoffman, who won an Academy Award for the film "Capote," was found dead in his New York City apartment on Sunday (February 2) in what a police source described as an apparent drug overdose.

Hoffman, 46, was found unresponsive on the bathroom floor of his Greenwich Village apartment by police responding to an emergency 911 call, and Emergency Medical Service workers declared him dead on the scene, the New York City Police Department said in a statement. An investigation was ongoing.

The New York Times, citing a law enforcement official, said investigators found a syringe in Hoffman's arm and an envelope containing what was believed to be heroin.

A police department source told Reuters that Hoffman had died of an apparent drug overdose.

Hoffman, who is survived by three children with his partner Mimi O'Donnell, had detailed his struggles with substance abuse in the past.