A memory stick containing sensitive Heathrow security data, including the Queen’s route to the airport, was reportedly found lying in the street.

A total of 76 files on the drive contained maps and restricted documents, reports the Sunday Mirror.

The USB stick, which was discovered by an unemployed man in north London, detailed the exact route the Queen takes to the airport and her security measures as well as those for cabinet ministers and foreign dignitaries, according to the newspaper.

It also reportedly contained other sensitive information such as a timetable of security patrols guarding against terror attacks and the types of ID needed for restricted areas.

A spokeswoman for the airport said an internal investigation has been launched into the data breach.

The newspaper says that the memory stick was handed to its reporters by a man who spotted it on the pavement in Ilbert Street, in Queens Park, as he made his way to a library to search for work.