James Gandolfini, the Emmy-winning actor who was best known for portrayal of a mob boss in TV series "The Sopranos", died at the age of 51.

Gandolfini was believed to have suffered a heart attack on Wednesday while vacationing in Italy.

Hollywood actor had been scheduled to attend the closing of the Taormina Film Festival in Sicily on Saturday.

He was taken from his Rome hotel to the city's Umberto I general hospital where staff found that his heart had already stopped at about 11:00pm local time (21:00 GMT), a hospital spokesman said.

Since "The Sopranos" ended its six-season run in June 2007, Gandolfini appeared in a number of big-screen roles, including "Zero Dark Thirty," a film about the hunt for Osama bin Laden, and the crime drama "Killing Them Softly".

At the time of his death, he had been working on an upcoming HBO series "Criminal Justice" and had two motion pictures due out next year.

Source: Agencies