LOS ANGELES: Emmy award-winning US actor James Gandolfini, the star of the long-running mafia drama “The Sopranos,” has died at the age of 51 in Italy, his managers said Wednesday.

The burly actor, who won three Emmys and a Golden Globe for his portrayal of mob boss Tony Soprano on the HBO series, suffered a heart attack, celebrity website TMZ and industry daily Variety reported.

“It is with immense sorrow that we report our client, James Gandolfini, passed away today while on holiday in Rome, Italy,” said a joint statement from his California-based managers, Mark Armstrong and Nancy Sanders.

“Our hearts are shattered and we will miss him deeply. He and his family were part of our family for many years and we are all grieving.”Gandolfini was in Italy for the Taormina Film Fest in Sicily, where he was expected to participate in a roundtable discussion with Italian director Gabriele Muccino this weekend, according to TMZ.

Tributes poured in from fellow actors, including Susan Sarandon, who tweeted: “So sad to lose James Gandolfini. One of the sweetest, funniest, most generous actors I've ever worked with. Sending prayers to his family.”

Jonah Hill wrote on the microblogging site: “I'm truly heartbroken to hear that James Gandolfini has passed away. He is one of my all time favorite actors. Tragic loss,” while Steve Carrell said it was “unbelievably sad news.””Awful awful news. James Gandolfini will be missed. He was a great actor. Just great,” actress Mia Farrow tweeted.

HBO, the cable TV channel on which “The Sopranos” aired, issued a statement saying: “We're all in shock and feeling immeasurable sadness at the loss of a beloved member of our family.”

The New Jersey-born actor had a long film and stage career before lending his heavy stature and big grin to play a depressed mafioso in “The Sopranos,”the celebrated series that ran from 1999 to 2007.

He began acting in the New York theater, making his Broadway debut in the 1992 revival of “A Streetcar Named Desire” with Jessica Lange and Alec Baldwin.

His breakthrough role came as a hitman in Tony Scott's 1993 “True Romance,”which he followed with “She's So Lovely” (1997), “8MM” (1999), “The Mexican”(2001), “The Man Who Wasn't There” (2001) and “In the Loop” (2009).

Last year, Gandolfini played former CIA director Leon Panetta in the Oscar-winning Osama bin Laden manhunt movie “Zero Dark Thirty,” and was seen in this year's comedy “The Incredible Burt Wonderstone.”

HBO managers praised the actor as “a special man, a great talent, but more importantly a gentle and loving person who treated everyone no matter their title or position with equal respect.””He touched s