A Tory press officer fled a Jeremy Corbyn Labour leadership rally after his cover was blown.
The man was approached at the event in Nuneaton by Channel 4 News reporter Michael Crick, who asked if he was "Mr Watkinson".
When challenged that he worked at Conservative HQ, the individual stood up and walked out of the building.
He was pursued to his car by the journalist, who suggested he might have been sent by Tory chairman Lord Feldman.
A Conservative Party spokeswoman said they were aware the staff member had been attending, and stressed it had been a public event.