London: On April 7, thieves using heavy cutting equipment broke into 60–70 safe deposit boxes in London’s Hatton Garden district, home to numerous diamond and jewelry wholesalers, according to a statement by the local Metropolitan Police.

Reports say that the thieves may have gotten as much as $300 million in gold and diamonds, which John Kennedy, president of the Jewelers’ Security Alliance, says would make it one of the largest jewelry thefts in history.

With most of the industry gone for the Passover holiday, the burglars broke into Hatton Garden Safe Deposit Ltd., which calls itself London’s leading safe deposit company. According to The Mirror, the thieves broke through a wall, climbed through an elevator shop, disabled the vault alarm, and then cut through its 18-inch door before being set loose on the safe deposit boxes.

The Telegraph reported that the gang stole the system hard drive that held closed-circuit footage, “suggesting some level of insider knowledge.”

Local sources say the group of boxes is considered well protected, and some wonder why the thieves targeted only a limited number of boxes out of the hundreds there.

It is also not clear why other alarms didn’t go off, though one jeweler told the press a security guard told him “he didn’t get paid enough” to check one ringing alarm.

Kennedy says that the incident shows that jewelers need to be extra-vigilant on holiday weekends, as that is when criminals often strike.

The Metropolitan Police said that the investigation is “a slow and painstaking process involving forensic examination, photographing the scene, and recovering exhibits in meticulous detail in order to preserve the evidence. Officers anticipate this process to take approximately two days.”