Brian Williams Brian Williams

Brian Williams encountered an unexpected interruption during his live NBC Nightly News broadcast — a blaring fire alarm.

"You'll forgive us, we have a fire alarm announcement going on here in the studio," he told viewers Tuesday evening as he began the program reporting on American Airlines' financial crisis.

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The alarm was merely a test, and Williams, a former volunteer firefighter himself, stayed calm amidst the interruption."We should advise our viewers there is no danger to us," he said. Check out the awkward live TV moment below: