Police are examining a photo that allegedly shows Top Gear host Jeremy Clarkson talking on a mobile phone while driving on a motorway.
Jeremy Clarkson is alleged to have used the phone at the wheel
Adam Blake, 22, and Hayley Byford, 21, claim they saw Clarkson on the phone as he did 70mph (112kph) in a 1970s Mercedes on the M40 in Oxfordshire.
A photograph taken by the pair was sent to the Daily Mirror newspaper, who handed it to the police.
Drivers caught using mobiles face three points on their licence and a £60 fine.
A spokesman for Thames Valley Police said: "We have been handed the photograph and we will be looking at it with a view to a possible prosecution.
"If we have got evidence we think could be supported in court, we will take action."
Clarkson has not released a statement on the incident.
The Daily Mirror said it confronted the host at his Oxfordshire home and he denied he had been talking on the phone.
After being shown the picture, the paper said he told the reporter he could not talk to them because he wrote a column for another paper.
A spokeswoman for the BBC's Top Gear programme said they would not comment because it was not a BBC matter.
Mr Blake was quoted by the Daily Mirror as saying: "We could not believe that we'd caught him out. My girlfriend saw he was on his mobile. She grabbed hers and took a picture of him."