Mary Mara has died after drowning, according to New York State Police.
The actress, best known for her role as Mrs Sullivan on Ray Donovan, was discovered on Sunday morning in the St Lawrence River in the town of Cape Vincent which lies about 90 miles north of Syracuse.
TMZ reports that police troopers responded to a call of a possible drowning at around 8am and found a body in the water on arrival.
It's thought Mary had been visiting her sister and was in the river doing exercise.
While her body has been taken for an autopsy, preliminary investigations reportedly showed no signs of foul play.
A representative of the star confirmed the sad news to Fox News Digital and told the publication: "Mary was one of the finest actresses I ever met. She had a terrific sense of humour and a unique outlook on life.
"I still remember the first time that I saw her onstage in Mad Forest in 92. She was utterly captivating, well loved, and will be missed."
The Syracuse-native graduated from Corcoran High School before attending San Francisco State University and Yale.
She went on to have a successful acting career.
Throughout her career, which spanned over three decades, Mary featured in over 20 movies and 40 television shows, such as West Wing, Law & Order: Special Victims Unit, NYPD Blue and Lost.
She also featured as Loretta Sweet on ER and Nance in Shameless, as well as taking up roles on hit shows Star Trek: Enterprise and Nip/Tuck.
Her last credit, according to IMDB, was a role in the 2020 film Break Even.
Tributes began to pour in for the star on social media following the news.
One Twitter user wrote: "So sad. RIP," followed by a praying hands emoji.
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