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Ritter, who was 54, collapsed on Thursday evening while filming "8 Simple Rules for Dating My Teenage Daughter," the ABC television comedy which had reinvigorated his career and was a centerpiece of the network’s upcoming fall season.

The former star of "Three’s Company" was taken to Providence St. Joseph hospital in Burbank, California, across from the studio where he had been working.

Surgeons at the hospital were unable to save him, and he died from a "dissection of the aorta," which results from an unrecognized flaw in a main artery from the heart, his publicists, Wolf-Kasteler & Associates Public Relations, said.

Ritter was best known for his portrayal of Jack Tripper in the 1970s situation comedy "Three’s Company," which won him Emmy, Golden Globe and People’s Choice awards.

A prolific actor, Ritter recently reconnected with television audiences as the star of "8 Simple Rules."

Ritter played Paul Hennessy in the family comedy about a father dealing with his precocious daughters which was one of the Walt Disney Co.-owned network’s hits in the 2002 season.

"All of us at ABC, Touchstone Television and The Walt Disney Company are shocked and heartbroken at the terrible news of John’s passing. Our thoughts and prayers are with his wife and children at this very difficult time," ABC said in a statement.

Born into a Hollywood family, John Ritter was the son of country singer and actor Tex Ritter and graduated from Hollywood High School, where he was student body president.

He graduated from the University of Southern California with a degree in drama and went on to act in film, television and on the stage.

He is survived by his wife, Amy Yasbeck and their daughter, Stella and three children, Carly, Tyler and Jason, from his first marriage to Nancy Morgan.