James Gandolfini has reportedly died while in Italy, according to Deadline.com.

According to the website, the “Sopranos” star was in the country for a film festival. Variety also initially reported that he suffered a fatal stroke, but both the trade site and Deadline.com updated the cause of death to a heart attack.

Gandolfini was 51 years old and is survived by a wife and two children. He became a household star for his portrayal of mob boss Tony Soprano on “The Sopranos,” a role which earned him three Emmys on six total nominations. “Absolutely stunned,” Chris Albrecht, the former chairman and CEO of HBO who greenlit “The Sopranos” told Deadline. “I got the word from [‘Sopranos’ star] Lorraine Bracco and just got off with [producer] Brad Grey who had just heard from [show creator] David Chase. We had all become a family. This is a tremendous loss.”

“We’re all in shock and feeling immeasurable sadness at the loss of a beloved member of our family,” HBO said in a statement to The Huffington Post. “He was 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 so many of us over the years with his humor, his warmth and his humility. Our hearts go out to his wife and children during this terrible time. He will be deeply missed by all of us.”

In addition to his standout television career, Gandolfini also appeared in a number of films, including “Zero Dark Thirty” and Chase’s directorial debut, “Not Fade Away.” More recently, he co-starred as a Las Vegas casino owner in the March comedy “The Incredible Burt Wonderstone” and had a small role in the indie film “Violet and Daisy.” The actor also finished work on the upcoming Tom Hardy film “Animal Rescue” and an untitled feature from director Nicole Holofcener.