The cause was pancreatic cancer, his lawyer told The New York Times.
Accomplished as an actor, dapper and irresistible to women, Gazzara came by his many streetwise roles naturally. Born Biagio Anthony Gazzara on Manhattan's Lower East Side, the child of an Italian immigrant carpenter and roofer got the acting bug starting at age 12, at the Madison Square Boys' Club. "My voice was this deep even then," he told PEOPLE in 1976.
The urge to perform "screwed up my schooling," he said, "because up until then I was a fantastically gifted student. I stayed out of school 54 days in a row and went to movies."
Briefly attending night school at City College of New York, before making his way to Erwin Piscator's Dramatic Workshop and the Actors' Studio, Gazzara then burst onto Broadway in three straight hit roles. These included the booze-deflated Brick in Cat on a Hot Tin Roof (the role Paul Newman played in the movie) and the junkie in A Hatful of Rain (Don Murray did the movie). Theater critics hailed him as the new heir to Humphrey Bogart or Marlon Brando.
When Broadway stage roles dried up, Gazzara moved to California and appeared in movies, including Anatomy of a Murder and The Young Doctors. He also played his most famous role on TV, as a doomed attorney on NBC's answer to ABC's The Fugitive. Called Run for Your Life, it ran from 1965-68.
Even before early professional success there was an early marriage, to actress Louise Erickson. The union lasted from 1951 until their divorce in 1957. "I was married at 21," he told PEOPLE. "What a moron I was! … It was that kind of romantic thing, built on nothing."
His second marriage, to actress Janice Rule, with whom he had a daughter, actress Elizabeth Gazzara, ran longer, from 1961 until their 1982 divorce. At the time of his death, Gazzara was still married to his third wife (since 1982), former model Elke Stuckmann.
Gazzara's later roles included those in movies directed by his close friend, the actor John Cassavetes, as well as in 1979's Bloodlines and 1981's They All Laughed, both of which costarred Audrey Hepburn, with whom Gazzara was romantically linked.
Even in his 70s and 80s, after having battled throat cancer diagnosed in 1999 and suffering a stroke in 2005, Gazzara remained active. He costarred with Nicole Kidman in the arty Dogville, and the Internet Movie Database currently lists him as filming two movies still in production.