Murfreesboro Police are investigating a robbery at the Smoothie King on Medical Center Parkway. It happened Monday night around 8:45 when a white male, in his 20's or 30's, asked a clerk to put money in a grey bag he was carrying. The clerks reported he told them he had a gun. The suspect is further described as about 6-foot, 200-pounds wearing a green t-shirt and a dark ball cap. If you have any information, contact the MPD detective division at 893-2717 or Crimestoppers at 893-STOP.