James Gandolfini, known for his portrayal of Tony Soprano on HBO's "The Sopranos," died from a reported heart attack last night in Rome at the age of 51.

According to New York Times, Gandolfini's death was confirmed by HBO. The actor passed away while vacationing and was scheduled to appear at the Taormina Film Fest.

"We're all in shock and feeling immeasurable sadness at the loss of a beloved member of our family," said HBO in an official statement.

"He was 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 is survived by his wife of five years Deborah Lin, his son Michael, and daughter Liliana.

Since the sudden tragedy, fellow "Sopranos" cast member Steven Van Zandt expressed his condolences on Twitter.

Maureen and I send our deepest sympathy and love to Deborah, Michael, Lily, and all of Jimmy's family.

— Steven Van Zandt (@StevieVanZandt) June 20, 2013

In addition, David Chase, the creator of the hit series, calls Gandolfini "a genius."

"Anyone who saw him even in the smallest of his performances knows that. He is one of the greatest actors of this or any time. A great deal of that genius resided in those sad eyes. I remember telling him many times, 'You don't get it. You're like Mozart'. There would be silence at the other end of the phone. For Deborah and Michael and Liliana this is crushing. And it's bad for the rest of the world. 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."

Joseph Gannascoli, who played Vito Spatafore on "The Sopranos," also sent his condolences. "Jimmy and I were not the closest of friends, but I am forever indebted to him. He came with his son and spoke at my wedding, came to my restaurant to meet fans sick as a dog in the rain and stayed for hours. He also said he would go in and talk to David Chase with me if I didn't want to play my role on the show. Just a humble and gifted actor and person."

Steve Schirripa, also known as Bobby Baccalieri during his time on the show, calls Jimmy "a dear friend and like a brother to me." "He was a great actor and a great father. I will miss him terribly. I am very sad." Maureen VanZandt, who played Gabriella Dante, is "honored to breathe the same air as him."

I loved James so much. He was a beautiful man and a genius. I was honored to breathe the same air as (cont) pic.twitter.com/j6JY8Rq50u — Maureen Van Zandt (@MVZaGoGo) June 20, 2013