By Ken MacLeod

BEVERLY (CBS) – Thieves are finding easy targets on the North Shore: Cars that aren’t locked with valuable items inside.

If your car door was unlocked, or an officer spotted your GPS, wallet, or something important in plain view, you might have found a warning on your windshield in Beverly this weekend.

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Police were willing to stir-up a little proactive controversy to warn folks they were easy targets for some very busy thieves. Any car doors they found unlocked they opened up and locked themselves for the owner. They admit they did get some angry calls from drivers — who left their keys inside their unlocked cars.

WBZ-TV’s Ken MacLeod reports

WBZ NewsRadio 1030’s Kim Tunnicliffe reports

The hunting ground includes neighborhoods and parking lots from Beverly to Gloucester to Rockport.

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“A few were upset by the fact that we went into their vehicles, and we understand it,” said Beverly Police Chief Mark Ray.

“It’s a little creepy, but I think that it has best intentions,” said one resident.

Beverly police wrote roughly a hundred warnings, alerting car owners to their shortcomings, and giving them some tips to keep thieves from ransacking their rides. Residents even got reverse 911 calls.

Gloucester detectives made some progress late Tuesday afternoon when they questioned several people at a house, after a tip led them to stolen items inside, including i-Pods and prescription medications swiped from cars just yesterday.

Police back in Beverly locked all the car doors they found open during their weekend campaign, hoping to change some very stubborn habits.

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Roughly one of every five parked cars police checked on over the weekend had either an unlocked door or open window.

Ken MacLeod