A police helicopter is being used to search for a man allegedly linked to a series of incidents in Tasmania's north-west, including a service station robbery.
Police said they were first notified about the man shortly after 9am on Sunday, when they received reports he was "acting erratically" on Macfie Street in Devonport.
They said members of the public reported he was "knocking on doors and demanding keys to their vehicles" before he left the scene in a white Toyota.
Police said a service station in Railton, about 22 kilometres south of Devonport, was robbed just before 10am, with a quantity of cash taken from the premises.
The man is then alleged to have stolen a silver Alfa Romeo from Kimberley, about 9 kilometres south-east of Railton.
Police resources, including a helicopter, have been deployed to search for the man and the stolen vehicle.
The suspect is described as being about 5 feet 8 inches in height, with short hair, olive complexion and facial tattoos.
Police said while no-one had been physically injured in any of the incidents, they are urging anyone who sees the man to not approach him but to contact police.
