Richard Griffiths Dies: 'Harry Potter' Star Passes Away At 65

British actor Richard Griffiths, best known for playing the curmudgeonly Uncle Vernon in the “Harry Potter” film series, has died. He was 65 years old.

Agent Simon Beresford made the sad announcement on Friday morning, stating that Griffiths had died on Thursday after experiencing complications from recent heart surgery, the Associated Press reports. Griffiths passed away at University Hospital in Coventry, England.

While Griffiths appeared in dozens of film and stage productions, he will be best remembered for his role as Uncle Vernon, the red-faced, unwilling Muggle guardian in the classic “Harry Potter” series.

"I was proud to say I knew him," "Harry Potter" co-star Daniel Radcliffe told the Associated Press.

Known for his large frame and larger stage presence, Griffiths was considered to be one of Britain’s most talented theatre performers. In 2006, he earned a Tony Award for his turn as Alan Bennett in “The History Boys,” a role he later continued in the film adaptation.

Renowned National Theatre director Nicholas Hytner, who directed Griffiths in “The History Boys,” called his performance "a masterpiece of wit, delicacy, mischief and desolation, often simultaneously,” AP reports.

Griffiths also gave an acclaimed performance in director Alan Bennett’s “The Habit of Art.” The "Harry Potter" actor was lauded for his memorable role as poet W.H. Auden, despite the fact that he did not resemble his subject.

The Associated Press fondly recalls Griffiths’ penchant for telling theatrical anecdotes, as well as his occasionally sharp temper. The veteran actor was known for publicly ridiculing audiences members when their ringing cell phones would interrupt his performances.

Radcliffe, who also starred alongside Griffiths in the controversial 2007 production of “Equus,” had more to say about his esteemed colleague.

"Richard was by my side during two of the most important moments of my career," Radcliffe told AP Friday.

“In August 2000, before official production had even begun on Potter, we filmed a shot outside the Dursleys', which was my first ever shot as Harry. I was nervous and he made me feel at ease.”

"Seven years later, we embarked on 'Equus' together. It was my first time doing a play, but terrified as I was, his encouragement, tutelage and humor made it a joy. In fact, any room he walked into was made twice as funny and twice as clever just by his presence."

Griffiths was born on July 31, 1947. According to the Associated Press, both his mother and father were deaf, leading him to learn sign language as a youth.

Griffiths is survived by his wife, Heather Gibson. The couple was married for 33 years.