Janesville police are reminding residents of personal security after a rash of vehicle thefts this week. Sergeant Drew Severson says in four cases the owners had left the doors unlocked with the keys still inside. Severson suggests residents go through an evening routine of removing valuables from vehicles, rolling up windows, removing the keys, and locking doors. He says all the thefts appear to be crimes of opportunity where the vehicle were stolen because it was easy. All the vehicles have been recovered.