The Ministry of Defense started an 'urgent' investigation after a cache with documents with sensitive military information has been found in a street in Newcastle.
Papers marked 'officially – sensitive' were discovered on March 16 from a black baket in Scotswood.
They contain details about the ranks of soldiers, switch patterns, E mail addresses, weapons data and access information for military facilities.
Downing Street said that 'appropriate action' would be taken after the discovery of the classified military documents.
The newspapers seem to relate to units based on Catterick Garrison barracks and among them was a sheet with 'Armory Keys and Hold Ids codes' -which is assumed to refer to an arsenal and intruder detection system.
Mike Gibbard, from Gateeshead, made the discovery as he was parking with Liverpool for the last collision of Newcastle United's Carabao Cup.

The Ministry of Defense started an 'urgent' investigation after a cache of documents with sensitive military information has been found in a street in Newcastle

Downing Street said that 'appropriate action' would be taken after the discovery of the classified military documents
“In the beginning I thought it was normal office material and someone had just dumped it on the industrial estate,” he told MailOnline.
'But when I passed and started to notice more paperwork, alarm bells began to ring. It wasn't something that should be there.
'The first part, that was torn, had the name of an army soldier who warned me about it. You could see that it was their ID number. '
The 41-year-old said he found more documents on the other side of the road and was alerted by the content.
“The more you looked, it was a cave of military documents from a Aladdin dumped on the path,” he added.
“I was very shocked, it's not what you expect to see when you go to a football match.”
Mr. Gibbard said that the articles contain extensive details about the layout of the base and the patrol area that could have been 'so dangerous in the wrong hands'.
He said: “Someone had torn it by hand and didn't even do it right. A4 -Bits were still merged and you could read all the information. '
He called 101 to report the discovery, but after waiting 15 minutes to take a handful of documents to police officers in the area to warn them.
Information security advisor Gary Hibberd said that the articles were an 'important' threat to those mentioned.
“They can easily be identified via social media, they may be forced, they can be harassed,” he told the BBC.
The documents were submitted in Northumbria Police and they were then given to the mod.
In a statement, a MOD spokesperson said: 'We are aware that documentation that reportedly relates to the department recently submitted to the police.
“We are investigating this urgently and the case is the subject of an ongoing internal investigation.”
A spokesperson for number 10 said: “The Ministry of Defense is currently looking at documents handed over to the police, but the case is the subject of an ongoing investigation by the army.”
Government guidance states that some 'official – sensitive' documents can pose a 'threat to life' when it is compromised.
It recommends that sensitive papers are destroyed with the help of shredders or 'burns'.