The UK's Defence Academy was hit by a cyberattack last year which caused “significant” damage, according to a retired high-ranking officer.

       Air Marshal Edward Stringer said the attack was possibly launched by a hostile foreign state such as Russia or China.

       Speaking to Sky News, Air Marshal Stringer said the security breach was discovered in March 2021 and the Defence Academy, which teaches thousands of military personnel, diplomats and civil servants each year, was forced to rebuild its network, with the damage yet to be fully rectified months on.

       Commenting on the likelihood of the attack being linked to a foreign government, like Iran or North Korea, AM Stringer said: “It could be any of those or it could just be someone trying to find a vulnerability for a ransomware attack that was just, you know, a genuine criminal organisation.”

       He said there were “costs to ... operational output” and “opportunity costs in what our staff could have been doing when they were having to repair this damage”.

       Recommended Thunderstorm warning as ‘sudden flooding’ and ‘lightning strikes’ to hit parts of UK ‘An icon at the time’: Daughter of first female Old Bailey judge reflects Exclusive: Government spent ￡700k on firm that advised Afghans not to flee

       “There are not bodies in the streets but there's still been some damage done,” he said, adding that the “unusual activity” was discovered by contractors working for outsourcing company Serco.

       He said there were “external agents on our network who looked like they were there for what looked pretty quickly like nefarious reasons”.

       Sky News reported that no sensitive information was stored on the academy's network. AM Stringer said the attack was not successful and while the hackers may have been using the academy as a “backdoor” to other Ministry of Defence (MoD) systems, there were no breaches beyond the school.

       An MoD spokesperson told Sky News: “In March 2021 we were made aware of an incident impacting the Defence Academy IT infrastructure.

       “We took swift action and there was no impact on the wider Ministry of Defence IT network. Teaching at the Defence Academy has continued.”

       The Defence Academy, based in Shrivenham, close to Swindon, offers courses to 28,000 people a year on themes including leadership, information warfare, cyber capabilities and international engagement.