Leaving your keys in a running car while it warms up on city streets is illegal in Wisconsin.Manitowoc police say this common winter habit creates opportunities for theft.Watch the full broadcast here: Police warn leaving keys i n running car violates state and local lawsI spoke with dozens of people about how they warm up their cars, and most told me they use remote start or smartphone apps. But for older cars that require a key, leaving it running with the keys in the ignition violates local law."We do have a city ordinance that prohibits you from leaving your keys in a running vehicle in a public place," said Paul Krock, crime prevention sergeant with Manitowoc Police.The Manitowoc city ordinance states that if your car is unlocked and the keys are in plain view on a public street or place, that's a violation."Unfortunately we've had cases where people leave their vehicles running with the keys in them and those vehicles are subsequently taken," Krock said.Police say these are typically crimes of opportunity."Somebody sees the car running with the keys in it or enters an unlocked vehicle, locates the keys and takes that vehicle," Krock said.In some Wisconsin cities like Milwaukee and Madison, leaving keys in a running car can result in a fine.The American Automobile Association says the number one risk is theft, but there are other reasons to avoid leaving your car running unattended."You're also going to use a lot of fuel efficiency. Sitting there idling is when your engine is the least fuel efficient. You will be burning money on gas," said Nick Jarmusz, AAA director of public affairs.Jarmusz says your car is ready to drive within a few minutes, so there's no need to idle or leave it unattended."From a mechanical standpoint the engine is safe and fine to start driving even when it's cold," Jarmusz said.AAA recommends bringing your hat and gloves and staying with the car."Even if it's still on the cold side, that's okay," Jarmusz said.Police say most car thefts are preventable. Their advice: lock it, take the keys, and don't give anyone an easy opportunity.This story was reported on-air by a journalist and has been converted to this platform with the assistance of AI. Our editorial team verifies all reporting on all platforms for fairness and accuracy. ...read more read less