Police departments across the country are participating in a nationwide campaign to remind people to lock their doors.

The Denville Police Department is the latest law enforcement agency to take part in the #9PMRoutine, a reminder for town residents to make sure that their car and home doors are locked by 9 p.m.

Denville police say that thieves broke into multiple vehicles in the Beacon Hill section of town between midnight and 6 a.m. Monday. All of the cars were left unlocked, according to officials.

“I guess people feel comfortable in their neighborhood and don’t think it will happen here. But it does,” says Denville resident Michael Mastanduno.

The #9PMRoutine effort urges people to set an alarm on their phone for 9 p.m. to make sure that valuables are taken out of cars and to lock their doors.

“I’ve heard it happening everywhere, not just in cities or suburbs,” says resident Chris McGugart. “When people aren’t thinking about it is when it happens the most.”

Denville police say that a car was stolen during the crime spree because a key was left inside the unlocked vehicle.

Police in Jacksonville, Florida say that they have been a part of the #9PMRoutine for about a year and have seen a 20 percent drop in auto burglaries.