Police are investigating an armed robbery that occurred Monday night at Sav-On Liquor & Wine, 915 N. Illinois Route 3, Waterloo.

The Waterloo Police Department responded to the business at 9:50 p.m. A male clerk inside Sav-On informed officers the robbery occurred approximately 15 minutes prior to the 911 call.

The clerk, who was not injured in the incident, reported a Black male dressed in dark pants, a black hooded sweatshirt, a surgical mask and gloves, entered the building and displayed a semi-automatic firearm. The clerk complied with his demands, police said, and the suspect left with cash from the register.

The suspect walked to and from the scene toward the area of Walgreen’s Pharmacy, which is just south of Sav-On.

The WPD asks anyone who may have seen the suspect before or after the incident to notify the department’s non-emergency line at 618-939-3377.