CHICAGO (CBS) — A string of effortless car burglaries in central DuPage County has caught the attention of police.

Wheaton Deputy Police Chief William Murphy said between Tuesday night and Wednesday morning, more than 40 vehicles were broken into.

“Every single one of them was an unlocked vehicle,” he said.

Murphy said such break-ins are easily preventable.

“They’re targeting specifically just the unlocked cars,” Murphy said. “They’re not shattering windows or punching locks. The easiest thing to do is to simply get in the strict habit of locking the car anytime it’s unattended. Whether it’s the middle of the day, or whether it’s overnight; if there’s nobody in it, you’re not using it, just keep it locked up.”

Glen Ellyn and areas near Lombard and Hinsdale recently saw a spike in similar incidents. Murphy said they’ve all been in contact, hoping to track down their suspects.