Actor James Gandolfini, best known for his role as Tony Soprano in HBO’s “The Sopranos” died of a heart attack today at age 51. According to the New York Times, “He was traveling in Rome, where he was on vacation and was scheduled to attend the Taormina Film Fest. The cause was not immediately announced; an HBO press representative said that Mr. Gandolfini may have had a heart attack.”

Courtesy HBO

Though he played characters with gruff exteriors, Gandolfini seemed like a gentle guy who preferred to keep his personal life personal. In many interviews, he seemed to have a self-effacing manner, and was always surprised that he’d made it as far as he had doing what he did. Sopranos creator David Chase said in a statement: “He wasn’t easy sometimes. But he was my partner, he was my brother in ways I can’t explain and never will be able to explain.”

Gandolfini is survived by his wife, Deborah Lin, and their 9-month-old daughter, Liliana, as well as a son from another marriage, Michael.