A gas station clerk stood up to an armed robber early Monday morning in Lexington.
Police say a man armed with a knife tried to hold up the Speedway on South Limestone near the University of Kentucky.
Police say the clerk backed up, told the man he had just pressed an alarm and the police were on the way.
A security guard with U.K. Hospital was in the store at the time and chased after the robber.
The suspect got away and didn't take any money.
Police reviewed surveillance video of the attempted robbery.
They hope it will help them considering the suspect was wearing a black mask.