Police are investigating after an armed robbery in Lake Macquarie.

About 6.15pm on, a man entered a bottle shop on Wilsons Road at Mount Hutton, threatening a 24-year-old staff member with a firearm.

He demanded cash before fleeing the scene in an easterly direction towards South Street, Windale.

Lake Macquarie Police District officers were called a short time later and established a crime scene.

The man is described as being between 180cm to 185cm tall, wearing dark clothing with his face covered.

Anyone who may have seen or heard anything suspicious in the area between 6pm and 6.30pm last night, or who may have CCTV or dashcam footage from nearby is urged to contact police or Crime Stoppers.