About 9:30 Saturday night a man drove up to a Missouri State Highway Patrol trooper on the highway to report he had been shot.
The trooper was at I-29 near 68th street when the man in his 20's drove up.
He was then transported to an area hospital with non life-threatening injuries.
Riverside police later determined the shooting occurred in the Argosy Casino parking lot a few minutes earlier.
Police are talking to the victim, trying to gather evidence in the parking lot, and checking for surveillance video, and what lead up to the shooting.
Anyone with any information is encouraged to call police.
