The One Show was taken off air because of a fire alarm.
The alarm sounded while presenters Matt Baker and Alex Jones interviewed actress Tamsin Greig.
As the noise continued in the background, the presenters looked bemused, with Jones saying: "Oh, I think that's our fire alarm. We'll link to a VT just in case."
The alarm then stopped and the presenters attempted to continue the programme, with Baker filling in time by joking: "What do you get if you cross cows and bats?"
A rather confused Greig answered with "battle?", as a cautionary announcement advising people not to use the lift could be heard.
As the alarm sounded for the second time, Jones then corrected Greig, saying "what you get is very happy bats" before saying "we're going to pop out, you're watching a VT". The daily magazine show was then cut short, with a recording of culinary show Simple Suppers filling the slot.
A BBC spokesman said there was no fire but the reason for the alarm at the BBC's White City studio in London was unknown. She said: "The One Show went off air tonight due to a fire alarm. We apologise to viewers for the interruption and normal service was resumed on BBC One as soon as possible."
Only a small number of BBC staff were evacuated. Afterwards Jones revealed what had triggered the alarm. She tweeted: "We're all safe and well! Somebody was warming their tea up and the microwave set off the alarm! That's live telly for you!"