BREAKING… Refresh for latest: Actor James Gandolfini died suddenly after a suspected heart attack while on holiday in Rome to attend the Taormina Film Festival in Sicily. He was 51. (UPDATE: The autopsy confirmed that Gandolfini indeed died of a heart attack.) Gandolfini will be forever known for his portrayal of mob boss Tony Soprano on the seminal HBO series The Sopranos, which eventually won him 3 Emmy Awards and a $1,000,000-an-episode paycheck. Overweight, balding, rough around the edges with a thick New Jersey accent, Gandolfini was the opposite of a marquee leading man, destined to be a character actor. Yet he proved through his masterful acting that he could make Tony Soprano sexy and smart, towering and powerful. Chris Albrecht who greenlighted the crime family saga at HBO in 1999 and approved Gandolfini in the role, just emailed Deadline: “Absolutely stunned. I got the word from Lorraine Bracco and just got off with Brad Grey who had just heard from David Chase. We had all become a family. This is a tremendous loss.” (Grey was the executive producer and Chase the creator of The Sopranos.) And Gandolfini’s managers confirmed the actor’s death. “It is with immense sorrow that we report our client James Gandolfini passed away today while on holiday in Rome, Italy,’ said 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.”

David Chase, the show’s creator, issued this statement today: “He was 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 [wife] Deborah and [children] Michael and Lilliana, 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.” Gandolfini reunited with Chase for The Sopranos creator’s feature film debut Not Fade Away, a 2012 drama in set in 1960s New Jersey in which the actor co-starred as the father of a teenage rock ‘n’ roll band lead singer. Fans anticipated a Sopranos movie from the pair, possibly a prequel about the Sopranos’ grandparents first coming to America from Italy and starring Gandolfini.

Brad Grey, The Sopranos‘ executive producer who’s now chief at Paramount, told Deadline: “Jimmy was one of the most talented, authentic and vulnerable actors of our time. He was unorthodox and truly special in so many ways. He had the sex appeal of Steve McQueen or Brando in his prime as well as the comedic genius of Jackie Gleason. I’m proud to have been his friend and grateful for the extraordinary years I was lucky enough to work with him. My heart and support goes out to his wonderful and loving family.” Added longtime Sopranos executive producer Terence Winter, creator/exec producer of Boardwalk Empire, “I’m truly crushed at the passing of my friend Jim Gandolfini. He was a gifted, fearless actor, respectful of everyone he met, and extraordinarily generous in every possible way.”

“I am shocked and devastated by Jim’s passing,” Gandolfini’s TV wife on The Sopranos, Edie Falco, said. “He was a man of tremendous depth and sensitivity, with a kindness and generosity beyond words. I consider myself very lucky to have spent 10 years as his close colleague. My heart goes out to his family. As those of us in his pretend one hold on to the memories of our intense and beautiful time together. The love between Tony and Carmela was one of the greatest I’ve ever known.”

Said Gandolfini’s therapist on The Sopranos, Lorraine Bracco: “We lost a giant today. I am utterly heartbroken.” His on-screen sister, Aida Turturro: “I’ve not only lost a great friend, but a true brother, on screen and off. James was the most generous actor to work with, but more so, a man with a heart of gold.”

Gandolfini’s fellow mobster on The Sopranos, Tony Sirico who played “Paulie”, had this to say: “Jim was one of my best friends in life, he was there whenever I needed him. Not only did he help me with my career, but also in life, god bless him. He and I were always helping the troops, we even went to combat zones to visit the Marines. He will be missed.”

HBO just told Deadline that it will put a card honoring Gandolfini after the episode currently airing on HBO Signature reading, “HBO mourns the loss of James Gandolfini, a beloved member of the HBO family.” The pay channel also released this statement: “We’re all in shock and feeling immeasurable sadness at the loss of a beloved member of our family. 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.”

Gandolfini was set to topline a new limited series for HBO, Criminal Justice, one of several projects he had in the works. Oscar winner Steve Zaillian is director/executive producer on the project and told Deadline: “I worked with Jim before The Sopranos and after it, and throughout these many years he has always been the same man. A real man, like they don’t make anymore. Honest, humble, loyal, complicated, as grateful for his success as he was unaffected by it, as respectful as he was respected, as generous as he was gifted. He was big, but even bigger-hearted. I’m so saddened to lose my friend, and sadder still for his family.”

Related: UNFINISHED BUSINESS: The Projects James Gandolfini Left Behind

Gandolfini’s portrayal of Tony Soprano was one of TV’s largest-looming TV anti-heroes — the schlub we loved, the cruel monster we hated, the anxiety-ridden husband and father we wanted to hug in midlife crisis when he bemoaned, “I’m afraid I’m going to lose my family. Like I lost the ducks.” In the most maddening series finale in recent history — an episode chock full of references to mortality (life, death, a William Butler Yeats reference to the apocalypse, a bathroom reference to a “Godfather” bloodbath) — his was the show’s last image, seen just as the words “Don’t stop” were being sung on the jukebox. It generated such extreme reaction that the series’ fans crashed HBO’s website for a time that night trying to register their outrage that it ended with a black screen, leaving them not knowing whether Tony Soprano had been whacked. (Related: THAAAT’S What We Were All Waiting For?) Lost co-creator Damon Lindelof referred to The Sopranos‘ infamous ending in his tribute to Gandolfini. “You created an icon. And you cut to black way too abruptly,” he wrote on Twitter. In large part to Gandolfini’s charisma (“Jimmy was the spiritual core of our Sopranos family,” Chris Albright, who is now CEO of Starz, noted today), that Season 5 of The Sopranos in 2004 remains the most watched series in HBO history with 14.4 million viewers on average.

Gandolfini’s breakthrough screen role came with his portrayal of Virgil, the philosophizing and woman-beating hit man, in Tony Scott’s True Romance. Though his list of credits including dozens of movies were dominated by his signature pay TV role, he parlayed his success in middle age into a broad Hollywood career in front of and behind the action in film, television and on stage. He remained in business with HBO and in 2006 signed a development deal with its film distribution company Picturehouse. In 2007, he produced the documentary Alive Day Memories: Home from Iraq, in which he interviewed 10 injured Iraq War veterans. He returned to the stage in 2009, appearing in Broadway’s God Of Carnage with Marcia Gay Harden, Hope Davis and Jeff Daniels. In 2010, Gandolfini produced another documentary, Wartorn: 1861-2010, in which posttraumatic stress disorder and its impact on U.S. soldiers and families was analyzed. More recently, he starred in the HBO film Cinema Verite and executive produced Hemingway & Gellhorn for the pay channel. After appearing on the big screen again in The Taking of Pelham 123 reboot and In the Loop, Gandolfini was in the recent features The Incredible Burt Wonderstone and Zero Dark Thirty.

Born in 1961 in Westwood, New Jersey, Gandolfini’s official bio says the Rutgers graduate spent years as a Manhattan bouncer and nightclub manager. He discovered his lifelong profession in the late 1980s when a friend took him to a Meisner technique acting class. He and made his Broadway debut in the 1992 revival of A Streetcar Named Desire with Alec Baldwin and Jessica Lange. His New York stage credits also included On the Waterfront, One Day Wonder with the Actor’s Studio, and Tarantulas Dancing at the Samuel Beckett Theatre. On film he was cast in small but pivotal roles as Geena Davis’ plumber boyfriend in Angie, a loyal Navy lieutenant in Crimson Tide, the enforcer/stuntman in Get Shorty. After he played the mobster in True Romance, it wasn’t long before his he made a living at it in The Sopranos. During the show’s 6-year run, he also won three straight Screen Actors Guild Award besides Emmys for lead drama actor.