Police in the Californian town of Truckee have warned car owners to lock their cars to stop bears breaking in.
Bears looking for food have been breaking in to parked cars and locking themselves in.
Sgt. John Mon Pere of the Truckee Police Department told ABC that little snow has led to less food for the animals, making them more adventurous with their search for something to eat.
"Bears can manipulate car handles if the cars are left unlocked," he said.
"After the bears go in, they may pull the door on themselves - that makes them stressed and causes them to thrash around, which can cause quite a bit of damage inside."
According to Sky News, there have been four incidents of bears becoming trapped in the past few weeks but no injuries.
On one occasion, a car owner managed to free a bear that got trapped and in another case police had to break a car window to let the animal out.
Once freed the bears ran into the woods around Truckee, which is home to 16,000 residents.