An on-stage routine by comedian Russell Brand prompted a police warning today about hoax or "frivolous" calls.
An audience at a theatre in Northampton saw the actor and presenter use a mobile phone to call the local force and claim he had spotted "the underpass attacker".
The prank call was inspired by local media coverage of investigations into a number of assaults in underpasses in the town in recent weeks.
In footage taken by one audience member and posted on the internet, Brand tells a Northamptonshire Police call handler: "It's regarding the attacks in the underpass. I have got some information for you.
"I have seen a gentleman who fits the description. He was wearing a light green top and polka dot trousers and I thought, well look at the state of him."
Brand was then put through to Northamptonshire Police's control centre in a call that lasted about three minutes.
Apparently able to hear the laughter of the audience at the Derngate theatre, the second force employee asked if he was making the call from home. The celebrity said the background noise was from his television and an episode of ITV drama The Bill.
The police staff member apparently ended the call as the comedian started to sing down the phone.
Northamptonshire Police would not comment on whether it was taking any action against Brand and refused to direct any criticism at the comedian.
But a spokesman said: "We would discourage anyone from making such hoax or frivolous calls."