Six cars were stolen from people's driveways on the same night in Greenwich.
Police told the Greenwich Time all six cars were unlocked with the keys inside when they were taken from homes Saturday night.
Lt. Louis Pannone said "people need to be responsible."
He said police are looking into whether Saturday's thefts relate to other cars reported stolen across the state.
Police later Tweeted that joyriding youths stole eight cars and all the recovered vehicles were damaged.