Authorities say the suspect walked behind the counter and removed an undisclosed amount of money from the till. He then assaulted the employee who was trying to stop him. The suspect then fled out the west door of the building.
The employee received some minor injuries, which did not require medical attention.
Police are searching for a black male in his 30s. He is described to be six feet tall with his hair in corn rows, wearing a black scarf over his face and a dark green sweatshirt.
An investigation into the case is ongoing.
Sioux Falls police are searching for a robbery suspect. Just before 1:00 AM this morning, a man held up the Jack Pot Casino on West 12th Street.