ROCKFORD - Rockford Police are investigating an armed robbery at a gas station Monday night.

At 11:30 p.m., police responded to Road Ranger, 5330 E. State Street, after an employee says a suspect walked in, showed a semi-automatic gun and demanded money.

The suspect left with an unknown amount of cash in a black SUV parked across the street. The SUV was last seen southbound on Newtowne Drive. No injuries were reported.

The suspect is described as a 17- to 20-year-old black man, 5'8" with a medium build, and wearing a black mask, black hooded sweatshirt, black pants and black shoes with white laces.