Launceston detectives are investigating a home invasion where two balaclava-clad men broke into a home and doused a mother and her two-year-old son with petrol.
The incident occurred in Kay Street, Kings Meadows, about 7.10am on Wednesday.
The robbers were looking for a man who was not home at the time of the invasion.
Acting Detective Inspector John Parker said in the process of attempting to locate the man, petrol was poured over the woman and her toddler.
Threats were made to harm the occupants and burn the premises down, police said.
The robbers did not locate the man, but they stole a quantity of cash before leaving the house.
The mother and her son did not sustain any physical injuries.
Police are calling for anyone with CCTV footage or who saw the two men near Kay Street to come forward.
Information can be provided to Tasmania Police on 131 444, or anonymously to Crime Stoppers on 1800 333 000.