Chinese agents are using drones to spy on the nuclear sub base in Faslane, say top brass.
They believe Beijing spooks are behind 18 drone sightings above UK military sites and power stations in just two years.
Faslane in Helensburgh, Dunbartonshire, is home to Trident submarines and nuclear weapons are stored at the Royal Naval Armament Depot at the same base.
The disclosure follows warnings by intelligence chiefs that China is attempting on stealing our most sensitive secrets.
The details of the drone activity were uncovered under freedom of information laws.
Lieutenant Colonel Philip Ingram, a former intelligence officer, said: “The Chinese have a very mature and sophisticated espionage program running throughout the UK.
“Business, academic research, manufacturers, supply chains, politicians, police, the military and civil servants and more are targets.
“Many will have been compromised, often without realizing what has happened.”
The Atomic Weapons Establishment in Aldermaston, Berkshire, where nuclear warheads are designed and made, is also said to have been targeted.
The sightings happened between 2019 and 2021 but details of the military bases were withheld for defense and national security reasons.
A report from one nuclear site said: “Security personnel reported a drone being flown close to a facility”.
Another said: “Drone landed in area and secured by security personnel.”
Yet another said: “Officer reported seeing a drone flying. No drone located upon further search.”
The revelation follows the disclosure earlier this year that Chinese spying in the UK was now MI5’s top priority.
One intelligence source said: “China is attempting to steal British secrets. There is a network of Chinese spies in the UK and they will use any means necessary to steal classified information.
“They have been targeting very sensitive establishments such as military bases and nuclear power stations by using drones.”
Last year it emerged that hundreds of serving and former members of the UK’s intelligence services face being targeted by Chinese agents.
A letter sent by MI6 security chiefs said Chinese spies are “aggressively” targeting British spooks and their families.
Sources said the Chinese Foreign Intelligence Service is using tactics such as offers of sex, theft and cybercrime.
The MoD said: “We have robust security measures in place at all defense sites, including nuclear bases, to respond to all such incidents.
“We continue to invest in a range of measures to tackle future threats, including counter-drone technology.”
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