Police are investigating a morning robbery on Monday at a Lexington fast-food restaurant.
Employees were opening the Richmond Road Arby's about 8 a.m. when a person armed with a knife entered through a back door, Lexington Police spokeswoman Sherelle Roberts said.
The robber demanded money from the safe and the cash register, and he left with an undisclosed amount of cash through the back door.
Officers were still interviewing witnesses at 9:30 a.m., Roberts said. They had not released a description of the robber.
Employees told officers the back door might have been left unlocked or propped open while employees were opening the store.