Police said the man entered the store on Wattle Road, Flinders and demanded cash at 8.30pm.

He stole cash and cigarettse and ran away towards Tabourie Close.

Police are looking for a man described as being about 30 to 40-years-old and 180 centimetres tall. 

He was wearing a brown hooded, long sleeve jumper with a grey symbol across the chest and down the arms, blue track pants with grey stripes, white running shoes, a baseball cap underneath the hood of the jumper, black and fluoro orange gloves, and a black backpack.

Police are appealing for information: Crime Stoppers, 1800 333 000.