The incident happened at an apartment complex near 76th and Lakeview late Thursday morning
Ralston Police Chief Ron Murtaugh tells 1110 KFAB officers were called to the Oaks at Lakeview apartments around 11:00 to check on a person down inside of a vehicle.
Murtaugh says the person was sleeping in the car and one of the doors was open. Murtaugh says as officers approached the driver woke up and put the vehicle in reverse.
The door caught the officer and knocked him to the ground. He suffered a minor head injury and was taken to the hospital.
Murtaugh says thanks to some alert witnesses, they have a photograph of the suspect and the vehicle and says it will only be a matter of time before an arrest is made.