A mammoth security breach in which highly sensitive information regarding Heathrow Airport was found in a memory stick in the street has come to light.

At a time when the threat of terrorism in the UK is severe, the 2.5GB USB stick with an abundance of classified documents with no encryption and no password to access it, is a huge "risk to national security."

The memory stick spotted in Ilbert Street, Queen's Park was handed to the Sunday Mirror by a member of the public after he saw the shocking amount of detail on it which could have taken years to compile.

Heathrow bosses have since launched an urgent investigation, The Mirror reported.

The confidential information contained an alarming 76 folders with maps, video and documents including the precise route the Queen takes when using the airport.

Other details included:

  • Files disclosing every type of ID needed – even those used by covert cops – to access restricted areas.
  • A timetable of patrols that was used to guard the site against suicide bombers and terror attacks.
  • Maps pinpointing CCTV cameras and a network of tunnels and escape shafts linked to the Heathrow Express.
  • Routes and safeguards for Cabinet ministers and foreign dignitaries.
  • Details of the ultrasound radar system used to scan runways and the perimeter fence.
The Queen opens Terminal 2 The Queen's Terminal, Heathrow.

The scare comes after multiple terror attacks this year, including the Parsons Green bombing last month as well as the attacks at London Bridge and Westminster .

A security source told The Mirror: “In the wrong hands this would represent a profound threat in terms of terrorism or espionage.

"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.”

Met Police detectives and airport chiefs are working together to find out how the USB drive, which could have ended up in the wrong hands, was dumped in the street.

Airport insiders revealed they were looking into whether there had been an “incompetent data breach” or if someone had been accessing files intentionally.

There is fear the data may have been copied and disseminated on the "dark web" where terrorists are known to buy information.

A police source told The Mirror: “The fear is that this information could have been downloaded and disseminated God knows where.

"The worry is it ends up on the dark web and used by bad guys to pick holes in airport security.”

USB stick

A former counter-terrorism chief who specialises in airport security told the Sunday Mirror: “There are serious questions to be answered.

“Why was this sensitive material held on an unencrypted memory stick and taken off site? It’s a huge security breach and massively embarrassing for those in charge of security.

"Knowing certain aspects of this ­information may make it easier for potential attackers to avoid detection.

“And the cumulative impact of having so many documents, videos, maps and images all in one place represents a security risk.”

The Sunday Mirror was contacted by an unemployed man who found the stick while on his way to the library to search the internet for work.

He said: “I was curious about what it contained so a few days later, when I went back to the library, I plugged it into the computer. All these files were there. I couldn’t believe it.”

The USB contained around 174 documents marked “confidential” or “restricted” – but could still be read.

An expert told The Mirror information on the memory stick could help facilitate an attack if it fell in the wrong hands.

Terminal 5 at Heathrow Airport

He said: “Knowing this information would cut down on surveillance and could potentially make access easier.

“Security chiefs will be working hard to ensure there is no physical threat as a result of this breach and changing processes if necessary.

"It is not helpful – certainly not best practice – to have maps and drawings of one of the UK’s biggest airports left in the street.

“It is serving up intelligence on a plate to people. It’s hugely embarrassing and should not have happened.

Heathrow launch internal investigation after USB stick with confidential security files was found on the pavement in Queen's Park

"In the wrong hands it could ­potentially be very helpful and would save them a lot of time in planning an attack.”

The Sunday Mirror has passed the file to Heathrow intelligence chiefs. The man who found it has been interviewed by airport security chiefs.

Insiders admitted it sparked a “very, very urgent” probe and that it posed “a risk to national security”.

One document highlighted recent terror attacks to illustrate the type of threat Heathrow could face.

Police at Heathrow Airport Terminal 4
Police at Terminal 4

It referenced the Leytonstone Tube stabbing in 2015, the Tunisia beach massacre which claimed the lives of 30 British tourists the same year, and the 2016 bombing in Istanbul’s Atatürk international airport.

The memory stick was found just days after US intelligence warned Islamic State jihadists and al-Qaeda are planning more mass-casualty attacks on the scale of the 9/11 hijackings.

A spokesman for the airport said: “Heathrow’s top priority is the safety and security of our passengers and colleagues.

"The UK and Heathrow have some of the most robust aviation ­security measures in the world and we remain vigilant to evolving threats by updating our procedures on a daily basis.

“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."

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