The excitable teens reportedly "thumped on the walls and rattled the windows" of the theater, where the 24-year-old actor was promoting his film "Kill Your Darlings."
"I've been dealing with it in various ways since I was 11," Radcliffe told the press. "I'm incredibly grateful for the swirl of support behind me. My fans seem excited by the unconventional path I am taking."
Radcliffe plays gay beat poet Allen Ginsberg in the film, which has garnered positive reviews from critics.
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The seventh and final "Harry Potter" book came out in 2007, while the eighth and final "Harry Potter" film came out in 2011. But time doesn't seemed to have dampened the enthusiasm of Boy Wizard fans who rushed to see Daniel Radcliffe at the Venice Film Festival on Monday.
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