Official files on £1.3bn Royal Navy submarine found in loos of Wetherspoons pub - report

Official documents about a Royal Navy submarine have reportedly been discovered in the toilets of a Wetherspoons pub.

Files about the £1.3bn "hunter killer" vessel called HMS Anson had been left in the loos at The Furness Railway in Cumbria, according to The Sun.

The paper said the documents appeared to show the inner workings of the submarine, and had been used by submariners who were training in how to isolate and depressurise elements of its system.

The Royal Navy said no classified information appeared in the papers.

Speaking to The Sun, a source said the venue was "packed" when the files marked "official sensitive" were found in the toilet cubicle, alongside a Royal Navy lanyard.

They added: "It was lucky a Russian spy didn't find them."

Barrow-In-Furness is home to a shipyard belonging to weapons developer BAE Systems, which is a short walk away from the pub in question.

It is where HMS Anson has been pictured recently - the fifth of a new Astute class of attack submarines which has joined the UK's naval fleet.

The Astute vessels are able to fire tomahawk missiles, and have been described by the navy as the "largest, most advanced and most powerful attack submarines" ever used.

A naval source said: "These documents enable submariners and contractors to understand how systems interact. They do not detail how they work, just that they exist."

They added the documents only contained simple designs of the on-board systems, without revealing how they work.

A Royal Navy spokesman said: "These are generic training documents that carry no classified information. However, we take all security matters extremely seriously and will investigate the circumstances of their discovery."