Detectives investigating the armed robbery of a fast food outlet in Maroochydore last week have released a comfit image of a man who may be able to assist with their inquiries.

Around 6.30pm on Wednesday August 26, a white Hyundai sedan was driven into the drive-through of the Aerodrome Road sandwich store.

The male driver threatened a female attendant with what appeared to be a firearm before forcing the employee to hand over a sum of cash from the till and driving away.

The man is described as being Caucasian in appearance, aged in his 30s or early 40s with short dark hair and a fair complexion. He was wearing a grey bandana with a black pattern across his face.

Investigators released CCTV images (pictured) of the vehicle last week and believe it may have been a white Hyundai Elantra, i40 or i45 sedan.