Police from Tweed/Byron Local Area Command are appealing for public assistance after a pharmacy was robbed at knifepoint overnight.

Police were called to the store on Wharf Street, Tweed Heads, about 6.45pm after a 25-year-old female store attendant was threatened by a man armed with a knife who demanded cash. The man was handed cash and he left on foot.

The man is described as being 20-25 years old, of Caucasian appearance with a fair complexion. He is about 180cm tall with a slim build and blue eyes. At the time he was wearing a blue hooded jumper which had a white trim, and black board shorts which had red stars. The man was also wearing a black balaclava.

Police patrolled the area immediately after the theft without success.

Tweed/Byron detectives are working with Queensland police as a man matching this description robbed a bottle shop in Coolangatta less than an hour later.