By Clark Collis
July 13, 2011 at 08:20 PM EDT
Didier Messens/Redferns/Getty Images

Dave Grohl has a reputation for being one of rockdom’s more genial inhabitants, and certainly I’ve always found the Foo Fighters head honcho to be an utterly affable interviewee.

But everyone’s rope has an end! Grohl reached his last night while playing a show at London’s Roundhouse venue, during which he stopped the Foos mid-song and demanded that some poltroon in a striped shirt be removed for allegedly fighting. Except the ex-Nirvana drummer didn’t use the word “poltroon.”

You can find out what word he did use in the expletive-filled footage of the moment below:

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