Security documents about the Olympics were found by a passenger on a train in Kent, it has emerged.

A commuter discovered the restricted file, said to contain policing strategy for the Games, in Dartford.

The sensitive information was handed to a national newspaper, sparking a Scotland Yard probe into how the dossier was lost. The documents have been returned to police after the bungle.

The Metropolitan Police insisted security for the London Olympics has not been compromised.

A spokesman said: "On Thursday 5 January a Metropolitan Police Service officer lost his bag containing a number of documents. The officer reported the loss to a senior officer. The Department of Public Safety have been informed as is routine.

"We do not believe that the bag contained operationally sensitive documents. The documents are now back in police possession.

"Obviously the loss of restricted material is a matter for concern, but we are satisfied that this does not compromise our security operation for the Olympics."

Are you the passenger who found the documents? Phone the newsdesk on 01634 227834.