A former civil servant has recalled the moment he found secret defence documents by the side of a road near Gravesend.

Victor Smith, now 73, had been walking by the A2 near the Pepperhill Roundabout in the 1980s when he stumbled across bags of confidential details about Royal Navy ships and submarines, and reported them to the police.

The Northfleet man spoke about his find following news of secret defence papers being discovered sodden at a Kent bus stop last weekend.

"It was about 35-40 years ago during the Cold War," he recalled. "It was a serious time, there was a lot of spying going on, and these documents had information about submarines in them.

"I've got a recollection that one of the submarines mentioned was a nuclear one. The cache was two or three large cloth bags at the side of the road.

"My guess is they were heading somewhere on their way for destruction and they fell off a lorry or whatever they were on. They were packed full of technical detail that if the Russians had got hold of they could have worked out all sorts of things about our weapons systems."

Also a keen archaeologist, Mr Smith is a former director of New Tavern Fort - the historic artillery fort in Gravesend - and acting chair of the Historical Defence Committee of Kent Archaeological Society.

"I was on my way to or from the Springhead Roman site and the excavations there," he added. "It wasn't far from the Pepperhill Roundabout and in those days they had a telephone box that was 400 yards away. "I was just intrigued - I thought 'what's this?' I then looked inside and my eyes almost popped out of my head."

"I didn't wade through all of the documents but I saw detail for equipment required for HM ships, including submarine parts and repairs to them, bits of ship machinery and equipment - so just the sort of thing that if you could interpret this stuff the Russians could have worked out all sorts of things.

"The interesting thing was the police could have said thank you for reporting to us - but they just said 'where?', and then it was 'right, now keep away from them.' Then they turned up and said 'buzz off' .

"There had been a bit of slip up, as there has with this recent one. I don't now how often it happens.

"I was surprised, shocked and worried - worried about whether other bags had fallen off and worries they might be looked at by an enemy."

It's not the first time Gravesend has been the location of such a find. In 2004 secret plans for the mass evacuation of London after a terror strike were found on a CD in a supermarket carrier bag, left on a train heading for Gravesend.

"I was surprised, shocked and worried - worried about whether other bags had fallen off and worries they might be looked at by an enemy..."

The 68-page dossier headed ‘Operation Sassoon - Metropolitan Police Traffic Plan for the Mass Evacuation of London’ - revealed how police would evacuate millions of people after a terrorist attack.

"Its another example of where you shouldn't leave stuff lying around," added Mr Smith who had a few words of advice for any other civil servants carrying secret information.

"I used to be in central government in the Department of Health," he added. "We had very sensitive documents and on occasion I would have to carry them from one place to another.

"If I was travelling by public transport they would be in a case on my knees. I would never put them in a luggage rack and if I was at a bus stop I wouldn't put them on the ground.

"You keep them on your knees and you keep your hands on the handle."

And he added: "Years ago if something like this was found your first port of call was the police - now the first point of contact might be the media.

"Perhaps people hope to get some money out of it. It makes you wonder how much it has happened before."

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