Police say an armed man who tried to rob a security guard at the Mount Gambier McDonald's Restaurant late yesterday morning may strike again.
They say the guard was carrying a bag with the morning's takings through the car park of the Penola Road fast-food outlet when he was threatened by a man brandishing a black semi-automatic handgun.
The guard refused to hand over the money and the assailant fled on foot.
Detective Sergeant Tony Scott says the man is still on the run.
"This male person hasn't been identified, nor has he been captured at this point in time, so we have a concern in relation to anyone that brandishes a firearm in a public place," he said.
Police are looking for a Caucasian man in his early 20s with a solid build, about 178 centimetres tall, with scruffy black hair and a scruffy beard.
He was wearing a black T-shirt and black pants.
