US actress Mary Mara, known from series such as "Emergency Room" or "Law & Order", drowned in the Saint Lawrence River, according to US police.
The 61-year-old was found dead in the river near her home in Cape Vincent, New York, on Sunday morning, police said on Monday (local time).
Preliminary investigations indicated that she drowned while swimming, the statement said.
There are no signs of a crime.
An autopsy will now determine the exact cause of death.
The St. Lawrence River flows from the Great Lakes to the Atlantic Ocean, crossing Canada and the United States.
Mara has played numerous television and film roles, including several episodes in series such as "Dexter" or "Star Trek: Enterprise".
She is best known for her roles in "Nash Bridges", "Emergency Room (ER)" and "Ray Donovan", as the US broadcaster CNN wrote.
Most recently, she was in front of the camera for the film "Break Even" in 2020.