Scotland Yard has begun an inquiry into how a secret dossier said to contain counter-terrorist plans for London's Heathrow Airport went missing.
The papers, found lying by the side of a road, reportedly showed 62 sites at the airport where the al-Qaeda group was thought most likely to launch anti-aircraft missiles.
The papers, which have now been returned to the Metropolitan Police, include key facts about escape routes, evacuation plans and road closures.
