'Harry Potter' stars Daniel Radcliffe, Emma Watson, Rupert Grint mourn Michael Gambon's death

"Harry Potter" star Daniel Radcliffe is paying tribute following the death of veteran actor Michael Gambon.

The actor's family said in a statement to the Associated Press Thursday, via his publicist, that he died following "a bout of pneumonia." He was 82.

Gambon was known to many for his portrayal of Hogwarts headmaster Albus Dumbledore in six of the eight franchise films. The Irish actor was cast after the death of his predecessor, Richard Harris, in 2002. Gambon started his role as the magical mentor in 2004 with "Harry Potter and the Prisoner of Azkaban" through the final film, "Harry Potter and the Deathly Hallows: Part 2."

Radcliffe, who played the titular character in the film franchise from childhood to young adulthood for its entire run, recalled starring alongside Gambon in the movies.

"With the loss of Michael Gambon the world just became considerably less fun," Radcliffe said in a statement shared with USA TODAY by his rep Thursday. "Michael Gambon was one of the most brilliant, effortless actors I’ve ever had the privilege of working with, but despite his immense talent, the thing I will remember most about him is how much fun he had doing his job.

"He was silly, irreverent and hilarious. He loved his job, but never seemed defined by it. He was an incredible story and joke teller and his habit of blurring the lines of fact and fiction when talking to journalists meant that he was also one of the most entertaining people with whom you could ever wish to do a press junket," Radcliffe said. "The sixth film was where I got to spend the most time working with Michael and he made the hours spent in front of a green screen together more memorable and joyous than they had any right to be.

"I'm so sad to hear he has passed, but I am so grateful for the fact that I am one of the lucky people who got to work with him," Radcliffe said.

Michael Gambon, veteran actor who played Dumbledore in 'Harry Potter,' dies at 82

J.K. Rowling, Emma Watson, Rupert Grint commemorate late 'Harry Potter' actor

"Harry Potter" author J.K. Rowling also remembered the actor Thursday.

"I've just heard the awful news about Michael Gambon. The first time I ever laid eyes on him was in King Lear, in 1982, and if you'd told me then that brilliant actor would appear in anything I'd written, I'd have thought you were insane," Rowling wrote in a post on X, formerly Twitter. "Michael was a wonderful man in additional to being an outstanding actor, and I absolutely loved working with him, not only on Potter but also The Casual Vacancy. My deepest condolences go to Michael's family and everyone who loved him."

Former co-star Emma Watson, who played Hermione Granger in the films, paid tribute to Gambon in an Instagram Story on Thursday.

"Kind kind kind Michael Gambon. You never took it too seriously but somehow delivered the most serious moments with all the gravitas," she wrote. "Thank you for showing us what it looks like to wear greatness lightly. We will miss you. xx"

Rupert Grint, who played Ron Weasley, wrote in a Thursday Instagram post that he was "so sad to hear about Michael. He brought so much warmth and mischief to every day on set."

He added, "He captivated me as a kid and became a personal role model of mine for finding the fun and eccentricities in life. Sending all my love to his family."

Fred Weasley actor James Phelps, 'Harry Potter' franchise pay tribute to Michael Gambon

James Phelps, who played Fred Weasley in the "Harry Potter" films shared a sweet memory with Gambon from their time together. "Whilst shooting 'HP6' I worked on the AD department for the whole shoot (apart from the days I was acting). And for that reason I spent many hours with Michael during the shoot," he recalled on X. "He was always very funny and very welcoming to share any knowledge he had."

"One day we were shooting Dumbledore's final clock tower scene, obviously quite an intense scene," James Phelps said. During breaks, James Phelps said he helped him and his twin Oliver Phelps (who played George Weasley), with their lines for a weekend gig. "It is a memory I've always has as one of the highlights of my 'HP' days."

"We are incredibly saddened to hear of the passing of Sir Michael Gambon. He brought immeasurable joy to 'Harry Potter' fans from all over the world with his humor, kindness and grace," the "Harry Potter" official Instagram wrote in a tribute. "We will forever hold his memory in our hearts."

Gambon's family remembered the late actor in a brief statement. "We are devastated to announce the loss of Sir Michael Gambon. Beloved husband and father, Michael died peacefully in hospital with his wife Anne and son Fergus at his bedside," they said.

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Eddie Izzard remembers 'how cool Sir Michael Gambon was'

Comedian Eddie Izzard took the opportunity to remember "how cool Sir Michael Gambon was − dancing (aged 76) to Victoria by The Kinks, in a break between shooting Victoria and Abdul" on X. Izzard included a video of the actor tapping his feet side to side with a cigarette hanging from his mouth while they were on set of the 2017 film.

Another former co-star, Ryan Phillippe, also took to X to share what it was like to work with the veteran actor.

"I was so lucky to work alongside Sir Michael Gambon in Robert Altman’s Gosford Park," he wrote. "Though he was in his sixties at the time and I was 25, we got along like schoolmates due to his irrepressibly youthful spirit.

"The car rides home from work, in his vintage convertible, at breakneck speed, with the Stones full volume on the radio, will stay with me forever."

Contributing: Anika Reed and KiMi Robinson, USA TODAY; The Associated Press

'Raise your wands': Social media flooded with tributes to Dumbledore actor Michael Gambon

This article originally appeared on USA TODAY: Michael Gambon death: JK Rowling, 'Harry Potter' cast mourns