Five men were sentenced to a total of 71 years in jail last week, more than a year after they attempted to pull off the world's biggest and most audacious robbery. Chief reporter ANDY LAITHWAITE details the attempted heist ...

THE GANG'S plan was to smash through the Dome, grab the diamonds from the high security vault and escape in a speedboat.

But a meticulously planned police operation, codenamed Magician, had been tracking some of the gang since a tip-off that summer.

Their goal was the De Beers Millennium Diamonds, 11 blue stones and the flawless 777 carat Millennium Star only second in value to the Crown Jewels.

Watched every step of the way, the raiders crashed a JCB through the side of the Dome, used a nail gun and sledgehammer to break the glass casings, and were only inches from the gems when police swooped.

Hours before the gang arrived, 200 police officers, including 40 specialist firearms officers had arrived at the Dome.

Dressed as cleaners and staff they waited for the gang to strike.

Gang leader Raymond Betson, right-hand-man William Cockram, Robert Adams and Aldo Ciarrocchi were snared inside the Dome.

Kevin Meredith was arrested as he waited in the speedboat.

The sixth member, Terence Millman, who died of cancer last year, was arrested north of the river, in the getaway van.

At the end of the three-month trial, DS John Shatford, who led the Flying Squad Operation, said: "They are ruthless and dangerous criminals with no care for anybody. They deserve nobody's glorification.

"Had it not been for the intervention of the police, they would have committed the largest robbery ever to take place in the world.

"The best information was the Russian Mafia were going to be involved. There were already deals with the Mafia. They (the gems) would have been out of the country very, very quickly."

Detectives believe leaders of the European crime syndicate ordered the gem theft through their contacts among British villains on the Costa Del Sol.

And for gang leader Ray Betson, a tobacco and alcohol smuggler who had close ties to ex-pat criminals, the raid was a once-in-a-lifetime opportunity.

And, if successful, they would have beaten the previous gem robbery record of US $43m of jewellery stolen from the Carlton Hotel, in Cannes, 1994.