SUN PRAIRIE, Wis. -

Sun Prairie police said a robber struck an employee in the head with the base of a handgun during an armed robbery Saturday night.

Sun Prairie police said they were dispatched to the Market Street Diner at 110 Market St. at 11:22 p.m. Saturday on a report of an armed robbery.

A man allegedly entered the business, pointed a handgun at an employee, and demanded money.

The man struck the employee in the head with the base of the handgun, causing minor injuries, police said.

Officers arrived and it was believed the robber may have possibly still been inside the business. A reverse 911 phone call was placed to residents in the immediate area as a precaution, police said.

Sun Prairie police, the Dane County Sheriff's Office, and the Wisconsin State Patrol coordinated efforts at the scene and determined that the man had fled prior to police arrival.

Police said it doesn't appear the man left with cash from the business.

The employee was treated for minor injuries and released.

Police said the robber was described as a black man with a skinny to medium build and a medium complexion, standing approximately 5-feet 10-inches tall. He was wearing a dark colored shirt and displayed a black semi-automatic handgun, police said.

Anyone with information on the incident is urged to contact the Sun Prairie Police Department at 608-837-7336 or the department tip line at 608-837-6300.