Photo:Getty

$100 dollar bills stock image

Getty

Very few people reportedly knew about the tens of millions in cash inside a high-security vault in the San Fernando Valley.

But on Easter Sunday night, a crew of highly sophisticated thieves shimmied through the roof of a Los Angeles money storage facility, and – without tripping any alarms or causing any noticeable damage to the outside of the safe – snatched as much as $30 million in cash,The Los Angeles Timesand theAssociated Pressreport.

The robbers slipped out undetected.

The facility only realized they were missing millions the following day, perThe LA Times, which cited Los Angeles Police Department Cmdr. Elaine Morales for an account of the burglary.

The Gardaworld facility in San Fernando Valley, Calif.ABC7

Gardaworld Sylmar San Fernando valley screengrab

ABC7

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Laura Eimiller of the FBI’s Los Angeles Field Office confirmed to PEOPLE that “a multi-million dollar theft” occurred in the Sylmar neighborhood of the San Fernando Valley on Sunday, March 31. Eimiller also says that agents are investigating the case jointly with the LAPD and are searching for “the person or group responsible.”

No arrests have yet been made in the case.

In a brief phone call Thursday, a spokeswoman for the LAPD declined to provide details on the case, citing the FBI as the lead investigative agency. Citing the “continuing” investigation, Eimiller declined to detail the heist, which is considered one of the largest cash thefts in the city’s history,The LA Timesreports.

No armored-car theft in the city has ever scored more cash, per the outlet, which reported that the facility stored cash for regional businesses.

A listing ofCalifornia addresseson the company’s website includes oneSan Fernando Valley-basedsecurity services facility, promising: “With our security guard services, rest assured that your people, property and assets are protected.”

“$30 million in the Valley, gone,” an unnamed GardaWorld employee told ABC7. “How? Why? I’m still trying to process it. Was it an inside job? Was it just one person? Was it a group? You know, there’s a lot of questions.”

A spokesperson for GardaWorld did not immediately respond to PEOPLE’s request for comment.

The heist comes less than two years after one of the largest jewel thefts in the country’s history, when a Brinks truck in Southern California was robbed of as much as$100 million in jewelsand other valuables – in a mere 27 minutes.

Those jewel thieves also remain on the run.

If you have information about the theft, you may contact the FBI at 1-800-CALL-FBI (225-5324) or online, attips.fbi.gov.

source: people.com