Queen Elizabeth
Credit: Mark Cuthbert/Getty Images

Heathrow Airport officials have launched an internal investigation after a memory stick containing sensitive security information was found simply lying on the street.

The information on the card, which was found by a member of the public, reportedly contained maps, restricted documents, and even information about the detailed security measures used to protect the Queen when she travels through the airport.

After finding the USB stick, the citizen first gave the information to the Sunday Mirror, which in turn alerted authorities. According to the Sunday Mirror, the stick contained a total of 76 folders with maps, videos, and ­documents about the airport. It was not encrypted and did not require a password to access. It also reportedly included detailed maps and information about the Royal Suite, which is used by the Queen as well as cabinet ministers when they travel through the airport.

“In the wrong hands this would represent a profound threat in terms of terrorism or espionage,” a security source told the paper. "Aviation security is under the microscope because of the desire by terrorists to bring planes down in a spectacular fashion. Security services would not want this leaked or sold to hostile parties.”

And while the stick has been recovered and delivered to authorities, it may be too late for the information to be contained.

“The fear is that this information could have been downloaded and disseminated God knows where,” a police source noted to the Sunday Mirror. "The worry is it ends up on the dark web and used by bad guys to pick holes in airport security.”

However, Heathrow officials appear to be unfazed by the discovery of the memory stick, telling CNN, "We have reviewed all of our security plans and are confident that Heathrow remains secure...We have also launched an internal investigation to understand how this happened and are taking steps to prevent a similar occurrence in future."