The cop who stirred the hornets' nest

Dave McKelvey, head of the crime squad in Newham, east London, vividly recalls the moment he believed a contract had been taken out to kill him and two of his officers.

"I remember literally going cold, a moment of sheer terror. Then a sort of controlled panic sets in," he says.

It was 2007 and Detective Chief Inspector McKelvey had spent the best part of his 25-year career with the Metropolitan police fighting organised crime in north and east London.

As McKelvey was interviewing a petty criminal, information was offered up that a well-known hitman had been contracted for £1m to kill three police officers.

This was not the first time officers had received intelligence that a huge contract had been taken out against individuals on their patch. But they had no idea who the targets were, or when the killings would happen.

Now Dave McKelvey was being told that an assassin with a sub-machine gun had been sitting in a car outside McKelvey's police station in Stratford for two weeks. The hitman was waiting for his chance to follow a particular car - one McKelvey believed belonged to an officer on his crime team.

"I immediately left and put a phone call in to his supervisor, who I knew was with him, and just said get him out."

And the other two targets?

"It was clear one of them was me," he says.

Panorama's Cops, Criminals, Corruption: The Inside Story, a special hour-long programme, is broadcast on BBC One on Monday 29 February at 20:30. You can catch up via the iPlayer.

McKelvey headed up a small team of young, enterprising detectives. They were taking on serious cases - big drug seizures, kidnappings, murders - and they were getting results not usually known for a borough outfit.

"We basically became a small cell operating against organised crime completely outside the system - outside the specialist departments, outside Soca [Serious Organised Crime Agency]," says McKelvey. "I know from the feedback that it caused chaos among the criminal network because they didn't know what was going on. We were taking out major criminals all the time and they couldn't work out who it was and why."

But among some officers, McKelvey was described as a "Gene Hunt on speed" - a reference to the old-style cop character in science fiction police drama Life on Mars and its sequel, Ashes to Ashes. McKelvey shrugs it off.

"I didn't go to work for the money. I went to work because I loved it. If there was a job on, I was the one who was the first person across the pavement. I was the one who put the door in," he says.

But McKelvey believes corrupt officers in the pay of an organised crime group instigated his downfall.

A routine raid in 2006 set off a chain of events that put him on a collision course with organised crime. And, he believes it ended up with the £1m contract being taken out against him.

It began at a scrap yard in the Docklands area of east London.

"It started as a small job. It was a search warrant for stolen metal at a scrap yard," he says. But it was something found at another address nearby which was to yield a bigger haul.

"We started searching this premises across the road which consisted of 42 big containers. As soon as we started opening up the containers we realised very quickly, it was an Aladdin's cave of stolen goods," says McKelvey.

"It was the spoils of 18 different lorry thefts, plus a commercial burglary. There was a load of counterfeit goods in there as well. I think it took us about five or six days to search the premises."

Three men were arrested and around £2m worth of stolen goods seized.

But intelligence from a source in the criminal underworld told McKelvey that he was now locking horns with an organised crime gang.

"I suddenly realised that all that work we'd been doing, there was an organised crime group who were sitting above it all looking down at what we were doing. We thought they were standalone pieces of work. In reality it was all being directed from above."

McKelvey got his team together.

"We put locks on the doors and I sat them all down and I explained to them that we were now investigating the biggest crime family in the UK."

Police intelligence linked the three arrested men to an organised crime group called the Hunt Syndicate. The man at the top was an East End businessman called David Hunt, who has a reputation for extreme violence.

McKelvey warned his team of young detectives.

"You will get potentially followed. They will undoubtedly make allegations against you. There is nothing these people will not do against you."

What he didn't know was that the crime group had been corrupting police officers for more than a decade.

Unbeknown to McKelvey, an informant at the heart of the Hunt Syndicate had been passing information back to the Met. Inexplicably, it seemed nobody was acting on it.

Several years earlier, a murder squad detective was handling this informant. Today he doesn't want to be named, but the detective says he was passing all the intelligence on to a squad that was targeting organised crime. But that squad, he says, denied receiving the information.

"When it reached the operational team it was not being actioned. They were saying they hadn't received the information," he says. "My suspicions were then that certain people were being protected."

"That team of officers I believe were corrupt and were actually in league with the [organised crime groups] they were supposed to have been targeting," he says.

Those "corrupt" officers were not connected with the officers who went on to investigate McKelvey himself.

Back in east London, McKelvey was building the case against the three men arrested at the scrap yard.

"We thought we'd hit the jackpot, we'd identified the principal handlers, we'd got the people who were actually handling the stolen goods," he says.

Then McKelvey heard about the threat to the police officers' lives. But he says it wasn't taken seriously by his superiors.

"There are set policies to deal with threat to life situations," he says. "They didn't do anything, they did absolutely nothing."

The hit was never carried out but the threat continued to hang over McKelvey and his team.

David Hunt says the intelligence about the hit was "plainly not credible". He says that he has never been arrested or questioned about any alleged contract to kill. He also says he was not suspected of involvement with the stolen goods.

The trial of the three men, however, did not go ahead even though McKelvey says the evidence against them was overwhelming.

It collapsed when an anti-corruption detective sent a dossier to prosecutors raising concerns about McKelvey and his team.

"I remember at the time just thinking I'm being fitted up," says McKelvey. "You just had nowhere to go, you just, you didn't know who to trust, you didn't know who to believe."

The corruption investigation into McKelvey, which went on for two years, was subsequently found to have been fatally flawed. Former Detective Chief Superintendent Albert Patrick was asked to review the allegations against McKelvey.

Patrick says it was difficult to work out exactly what McKelvey was being accused of. He says it was being alleged McKelvey had "an unhealthy relationship with the people he was actually looking at and arresting".

However, he couldn't conclude whether corruption had played a part in the investigation of McKelvey.

McKelvey was exonerated, but his career was over. The detective who had racked up 60 commendations left the force in 2010 suffering a breakdown.

While accepting he had no hard evidence, to this day he believes his investigation into organised crime had been deliberately derailed.

Since leaving the force, McKelvey has seen evidence that organised crime could have deliberately compromised his investigations.

In 2002 a secret Met report called Tiberius had clearly warned that some officers were in the pay of crime groups - including the Hunt Syndicate.

Tiberius, which concentrated on north and east London, concluded that: "Organised crime is currently able to infiltrate the Metropolitan Police Service at will."

It found murder investigations had been compromised, and that eight major crime syndicates had corrupted a total of 22 former and 34 serving police officers.

The report was so secret only the Met's most senior officers got to see it. Front line detectives like McKelvey, were left in the dark. The Met says it won't comment on his case.

They do say organised crime remains their single biggest threat. There are now approximately 6,000 organised crime groups in the UK.

"We are an organisation that probably deals with more organised crime group investigations than any other that you are likely to find, certainly in this country," says Martin Hewitt, a senior police officer with responsibility for professionalism and anti-corruption.

"We are absolutely alive to the threat that organised crime groups pose and absolutely alive to the fact that any decent sensible organised crime group will be trying to corrupt police officers."

The Met also says it has changed the way it works to make it harder for organised crime to ensnare police officers in corruption.

McKelvey sued the Met. In January, he received a substantial payout and an apology from his former employers.

He now lives with round-the-clock police protection.

Panorama's Cops, Criminals, Corruption: The Inside Story, a special hour-long programme, is broadcast on BBC One on Monday 29 February at 20:30. You can catch up via the iPlayer.

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