A multi-million-dollar heist in London’s jewelry quarter was likely carried out by a team of a dozen "professionals" with inside knowledge of the vault they robbed, according to a former diamond thief.
Larry Lawton spent 11 years in prison in connection with several jewelry robberies but now educates youngsters about the dangers of crime.
He told NBC News the daring heist in London represented the "score of a lifetime."
Police are still trying to determine how the thieves robbed the vault in the British capital just after midnight on April 3 and made away with some 70 safety deposit boxes. The contents of the haul has not been officially disclosed — but estimates in the British press have been as high as $200 million.
"I think they had it planned to the tee," said Lawton, who runs the Reality Check Foundation, a Palm Bay, Florida-based charity helping young people at risk of turning to crime. "You could see the men in the videos were professional. They had a purpose, they weren't hesitating, they all had a job to do," he said, referencing security camera footage of the raid.
Lawton believes the crew was split into at least three teams. According to his assessment of details released by officials, around six people likely broke into the vault with several others acting as look-outs on the street and at least one "fence," a criminal who trades in stolen goods on the black market.
"You’re talking about a dozen people in my mind," he said.
He also believes it was an inside job. "I would not break through a wall not knowing that on the other side they had some lasers…that would set off an alarm," he said. "I wouldn't rob that — I don’t think any professional would."
Security camera footage showed the robbers, disguised as construction workers, enter the building through a side entrance. They climbed down an elevator shaft and used industrial tools to break through almost seven feet of reinforced concrete into the basement vault.
An alarm did go off — and London's Metropolitan Police says it is looking into why officers did not respond.
By the time police finally arrived at the scene on Tuesday, the thieves would have likely "gotten rid of the diamonds right away," Lawton said. "They’re probably in a different country — I doubt seriously that they are in London right now."
But despite this meticulous planning, the reformed robber believes the people who carried out the audacious raid will be caught.
"There’s an old saying in prison, 'Three can keep a secret if two are dead,'" he said. "There are just too many people who know too much. I’m not a big believer that all these people can keep one big secret."
