Mary Mara

‘ER' Actor Mary Mara Drowns in New York River

Police believe the actor, 61, drowned while swimming in the St. Lawrence River

Mary Mara during 2006 Los Angeles Film Festival - "Swedish Auto" Screening at Crest Theatre in Los Angeles, California, United States.
Matthew Simmons/WireImage File - Mary Mara at the 2006 Los Angeles Film Festival at Crest Theatre in Los Angeles.

Mary T. Mara, a veteran of television dramas including "ER," "Nash Bridges" and "Law & Order," was found dead in a river, New York State Police said Monday.

Police believe the actor, 61, drowned while swimming in the St. Lawrence River in the town of Cape Vincent on Sunday morning, state police said in a statement.

State troopers and Cape Vincent emergency medical service workers made the discovery after 8 a.m., they said.

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