A man armed with a sawn-off rifle has held up a Launceston service station.
The man demanded money from the till.
He fled the scene with a small amount of cash and property, police said.
The incident happened about 11.05pm on Thursday.
The man is described as being about 25 years old, 165 to 170 centimetres tall, with fair skin and no visible tattoos.
He was wearing dark pants, a long-sleeved black top, white sneakers and a black cap with a reflective patch on the peak.
Police are asking anyone who may have seen a person matching this description to contact them.
They are also appealing to witnesses who may have observed a vehicle driving erratically in the area of Wellington, Frederick and Bathurst streets at that time, particularly a dark green coloured sedan.
Information can be provided anonymously by calling Crime Stoppers on 1800 333 000 or online at crimestopperstas.com.au