Portland police are investigating a string of commercial burglaries at five locations around the city.

The incidents were reported between Jan. 9 and 17. Burglars entered through windows where fans or air conditioning units had been installed and stole cash and copper, the Portland Police Department said Wednesday in a news release.

The police department is reminding businesses to lock their windows and pay attention to security alarm notifications. In some cases, the wires to security systems were cut and the crime wasn’t discovered until employees arrived to work the following morning.

“If you do not have a security system installed, it is a good idea to do so,” the release said. “Police are urging business owners to request a police response to any alarm notifications they might receive and to not ignore notifications of issues with their alarm systems.”

Burglaries were reported on Forest Avenue, Hanover Street, Union Street, Warren Avenue and Washington Avenue.

Anyone with information on the incidents may contact police anonymously at 207-874-8584 and leave a message on the department’s crime tip line or text “PPDME” with the message 874411 (TIP411).

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