Frank Vincent, best known for portraying the ruthless mob boss Phil Leotard on The Sopranos, has died at the age of 78.

His former co-star Vincent Pastore announced the news on Facebook earlier today, as did John Gallagher, who directed Vincent in Street Hunter, The Deli, and Animal Room.

"Another devastating loss — my close friend and colleague of 30 years Frank Vincent has left us," Gallagher wrote. "I could write a book about my times with Frank, all beautiful joyous memories, but today in our grief thoughts race to his beloved wife Kathy and his grown children. Requiescat in pace FV, see ya on the other side, love always JG."

According to TMZ, Vincent suffered a heart attack last week, after which he was hospitalized. He underwent open-heart surgery today, and died due to complications during the surgery.

He is survived by his wife and three children.

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