Actor James Phelps, who starred as Fred Weasley in the blockbuster Harry Potter fantasy films alongside his twin brother Oliver as George, injured Mike Newell during a play fight whilst filming the fourth movie of the series.
The 79-year-old filmmaker recalled, "We were doing the scene when Fred and George were rejected from entering the Tri-Wizard tournament."
Speaking on the special Harry Potter 20th Anniversary: Return To Hogwarts, which celebrated the release of the first film based on the best-selling books by acclaimed author JK Rowling, Newell explained that he intervened to encourage the boys to fight which left him in agony, reports femalefirst.co.uk.
He said, "These two were sort of prissying about at it and I said, 'No, come on boys, it's a fight'. I was a tubby 60-year-old gent at that stage and I really shouldn't have done it."
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"I remember gripping him round the waist and trying to fling him about and so forth and I cracked a couple of ribs. I was in absolute agony from then on, but of course, the wonderful thing was that I'd made a complete twit of myself and everybody felt much better for that."