In a plot three years in the planning, a gang broke into the vault of the Hatton Garden Safety Deposit building during the long Easter holiday weekend last year.
On the evening of April 2, the gang met at the building and were let in through a fire exit by a red-haired man known as "Basil", who has not been identified and is still at large, with a £20,000 (S$41,000) reward on his head.
Although they disabled alarms as they went, one was triggered. A security guard who went to the scene saw nothing untoward and the police failed to send any officers, a mistake for which they have apologised.
Disguised as gas workers and wearing hard hats, the group rappelled down an elevator shaft, then used a diamond-tipped industrial drill to bore three large holes in a 50cm-thick concrete wall. But they could not get inside initially because a cabinet containing deposit boxes was in the way.
The next day, the gang returned with new machinery, forced the cabinet out of the way and climbed into the vault, where they opened 73 of the 999 boxes, stealing jewels, gold and cash worth £14 million.
When police arrested the gang, they found a small smelting machine, diamond-testing equipment and tools to separate gold from diamonds.
REUTERS, AGENCE FRANCE-PRESSE