A sawn-off rifle, a young male, and a demand for cash confronted BP Launceston in Wellington Street late last night.
Around 11:05pm last night, a dark green sedan pulled into a dark parking lot at the rear entrance, pausing briefly in a park.
A solitary figure exits the car from the backseat and lumbers past an unknown CCTV camera.
The service station was deserted, except for one attendant and one customer when the man entered, brandishing a sawn-off .22 rifle and demanding money from the cash register.
Unexpectedly, 'he's actually been quite polite about it' says Inspector Philippa Burk from Tasmania Police.
The gunman pocketed a small amount of cash and cigarettes before fleeing around five minutes after entering.
WATCH: The gunman exits the car before committing the armed robbery at BP Launceston. VIDEO: Tasmania Police
A description released of the perpetrator puts him at approximately 25 years old, 165-170 centimetres tall, fair skinned and with no visible tattoos.
He was dressed in dark pants, a long sleeved black top, white sneakers, and a black cap with a reflective patch on the peak.
Police are appealing for anyone who may have seen a person matching this description to contact them.
"At this point in time we haven't been able to positively identify who it is, but we will continue working on it until we do," Inspector Burk says.
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.
Inspector Burk says the theft is only one casualty of the robbery.
"Obviously you can't count for the emotional trauma and the toll that it takes on staff members like this," she says.
She urges the public to make a report of any knowledge of illegal firearms to avoid these situations in the future, adding that it can be done so anonymously.
The investigation remains ongoing.