ASPEN, Colo. -- An Aspen restaurant owner found a way to keep bears from breaking into his outside walk-in freezer: an electrified mat gives them a mild shock if they try to open the door.

Bill Dinsmoor said he's had no bear trouble since he installed the mat at his Main Street Bakery & Cafe. Before that, bears broke into the freezer four or five times.

Dinsmoor said the shock isn't strong enough to hurt the bears, and humans won't get a jolt unless they're barefoot.

He said the Division of Wildlife loaned him a mat as an experiment. When agents took the mat to be used at a private home, Dinsmoor bought his own.

Division of Wildlife spokesman Randy Hampton said electric fences and mats can deter bears but they don't work in every situation.

Electric fencing has been typically used to keep animals in but it is becoming more popular as a bear deterrent, according to the Aspen Times newspaper. It's used to protect landfills and trash cans in other communities, as well as by backcountry campers.

A bear that stole meat from a home freezer in Snowmass Village found an electric mat when it returned. Animal services officer Laurie Smith said the home owners witnessed the bear get a shock. The bear hasn't been seen since.