By Diana Rocco

CALN Twp., Pa., (CBS) –  Police are investigating a burglary spree in Chester County.

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At least 12 businesses have been hit in the overnight hours.

As CBS 3’s Diana Rocco explains, the thieves break glass, and head right for the cash.

Two smash-and-grabs in Caln Township are the latest in a rash of business break-ins throughout Chester County.

“We assumed we’d be OK with lights on and stuff, but it just didn’t matter, they don’t care,” Bob Dyer of Dyer’s Deli said.

Twelve businesses have been hit since the new year. Bob Dyer from Dyer’s Deli in Parkesburg says someone broke in a week and a half ago after close.

“They took a hammer or something and tried to break the front door. Couldn;t succeed. He went in through the dining room window, climbed in, did a quick grab, tried to pry an ATM off the wall,” Dyer said.

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The thief got away with a laptop and some change, but left the Dyers with the repairs.

“The second day of the new year we’re already in the hole $1,000,” Dyer said.

Then it was LC Auto Body and Chester County Beverage all on Route 30. Police released this photo from the beer store’s security camera, but they aren’t sure it’s related to the others.

Monday night in Caln Township, Caln Pizza and Wings To Go on the Lincoln Highway had their windows busted and money stolen.

In all, the thieves have cost businesses up to $15,000 in damage and stolen items.

Now Dyer isn’t taking any chances. He’s installed security cameras and is one of several businesses looking out for each other after the local police go off duty at 11 p.m.

“We have agreements that it doesn’t matter what time of the night it is, we’re all leaving our phones on at night,” Dyer said.

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Police believe they know who their suspect is in at least one of these burglaries. But they’re asking area businesses to be on the lookout, keep the businesses well lit even after they close and to report anything suspicious.