NEW YORK (CNN) -- Actor Heath Ledger was found dead Tuesday of a possible drug overdose in a Lower Manhattan apartment, the New York Police Department said.

Heath Ledger was found dead in his Manhattan apartment.

The Academy Award nominated actor was 28.

"Pills were found in the vicinity of the bed," police spokesman Paul Browne told CNN.

"This is being looked at as a possible overdose, but that is not confirmed yet."

Ledger was found by a housekeeper who had gone to wake him for an appointment with a masseuse in the Soho apartment, Browne said.

He was declared dead at about 3:30 p.m., Browne said.

In 2005, the actor played Ennis Del Mar in "Brokeback Mountain," about two cowboys who had a secret relationship.