Jewellery worth tens of thousands of pounds was stolen when raiders broken into Europe's largest urban shopping mall, west London's Westfield Centre, in the early hours of yesterday.
A gang of up to 10 thieves used sledgehammers to break into the complex before attacking branches of De Beers and Tiffany & Co.
Security guards and police were alerted by electronic alarms but the gang escaped in several cars about 1.20am. No one was injured during the raid.
Officials at Westfield, which opened in October 2008 and has more than 250 shops, said it was the first burglary of its kind to take place in the centre. However, it is just the latest in a series of smash-and-grab attacks on jewellers and luxury stores across the capital.
Goods worth more than £4m were taken as thieves targeted Watches of Switzerland, Cartier, Dolce & Gabbana and Tiffany and Co. In one raid on the Mozafarian store in Knightsbridge last August, gems worth more than £1m were stolen in less than a minute.
The Westfield shopping complex pays for its own private security staff and police teams under an agreement with Hammersmith and Fulham Council.
Senior officers were so concerned about the amount of crime that may take place at the centre they agreed to build extra police cells before it opened.