Award-winning actor Philip Seymour Hoffman was found dead in his apartment in New York City on Sunday.
Two law enforcement sources told the NBC affiliate that Hoffman was found in the bathroom of his home in New York's West Village neighborhood. They characterized the death as an apparent overdose.
Earlier, the Wall Street Journal reported that the New York Police Department is investigating, and the Office of the Chief Medical Examiner is to determine the exact cause of death.
A police source said Hoffman was found dead after a 911 emergency call from a friend of the actor. The source gave no further details.
Hoffman won the Academy Award for Best Actor for the 2005 biographical film Capote, and received three Academy Award nominations as Best Supporting Actor.
-By CNBC.com. Reuters contributed to this report.