Roy Shaw: "You can't be a rascal all your life"

Now 64, he and his former associates gave up crime several years ago.

He says: "As you get older you can't continue to be a rascal all your life.

"You have to settle down so I've got my business and come out this way, they now live down here."

For many years criminal gangs have carried out their activities in Essex, relatively unchecked. But now the police and Customs & Excise are waking up to the size of the problem.

Vincent Harvey, from the National Criminal Intelligence Service (NCIS), says: "Probably about half of the major crime families are focused here and just about every other group has a connection to them.

These are thoroughly unpleasant people who don't mind using any technique if it furthers their own cause

Vincent Harvey, NCIS

You have to accept these are thoroughly unpleasant people who don't mind using any technique if it furthers their own cause."

Despite this, reported crime in Essex is among the lowest in the country. Some believe this is because intimidation keeps a lot of people silent.

Shaw talks about someone who informed on him many years ago.

Roy Shaw: Once 'the most dangerous man in the penal system'

"It was a close mate of mine as it happens, but he turned out to be a grass, so I broke a Brylcreem bottle and it was shaped like a knife, I got into the wing, pulled it and cut his throat."

For those who do start talking to the police, their lives are automatically put at risk.

New identity

Darren Nicholls was involved with a gang of drug traffickers, but decided to turn supergrass after three men were shot dead in a lane near the Essex village of Rettendon.

He gave evidence at the trial of two men - who were jailed for life for the murders - but had to be moved out of the area, with his wife, and given an entirely new identity.

Speaking from a police safehouse he said: "Essex is a lot rougher than people believe.

"They all think its a quiet villages, but it's the total opposite, it's an ideal place for crime and drugs, all round it's nothing like people expect, it's a very violent place".