An off-duty Clinton police officer was killed last night (Sunday) in a traffic accident in eastern Iowa. 39-year-old Rodney Powell was riding his motorcycle on Highway 67, north of Clinton, when he collided with a car about 6:10 P.M. Powell was airlifted to Genesis East Medical Center in Davenport where he later died of his injuries. The driver of the car, a 40-year-old from Savanna, Illinois, was not reportedly hurt. Powell had been a member of the Clinton Police Department five years.