SIOUX FALLS, S.D. (KELO) — The Sioux Falls Police Department is investigating an overnight armed robbery at the Black Diamond Casino in western Sioux Falls.

The suspect entered the casino and threatened an employee with a black pistol, demanding money.

After getting the money, the suspect ran from the business. He is described as a 6-foot tall man wearing all black clothing. No one was hurt.

The incident is under investigation.