The Ministry of Defence (MOD) is reviewing reports that classified information has been leaked online outlining the specifications of the British Army's Challenger 2 Tank.
A player of the video game 'War Thunder', who claimed to have been a real life Challenger 2 tank commander and gunnery instructor, allegedly posted the document in order to improve the accuracy of the design of the tank online.
The website UK Defence Journal said that the player claimed game designers had failed to "model it properly" and the tank needed to be adjusted.
To support his argument, the player reportedly posted pages from the official Challenger 2 Army Equipment Support Publication – a manual and maintenance guide.
The player identified the documents as belonging to a tank in Tidworth Garrison in Wiltshire, home barracks of the Royal Tank Regiment which operates Challenger 2 tanks.
Extracts from the documents, some of which were heavily redacted, appeared to show some documents had their "UK RESTRICTED" label crossed out and a stamp of "UNCLASSIFIED" added.
War Thunder is a popular video game in which thousands of players around the world can simultaneously control aircraft, ground vehicles, and warships from the United States, Germany, Russia, Britain, China and other countries.
An MOD spokesperson said: "We take all unauthorised disclosures of information extremely seriously.
"This incident will be reviewed and, if appropriate, an investigation will be launched, and mitigations put in place to prevent reoccurrences.
"We do not comment on leaked documents."
Cover image: A Challenger 2 Tank taking part in Exercise Spring Storm 19.