A 35-year-old Burnie man, who killed another man and injured a woman before taking his own life in Devonport on Saturday, used an illegal firearm and was unlicenced.
Police are searching for the source of an illegal Winchester shotgun, which they said the offender, Paul Carey, acquired in the past three months.
He killed Christopher Walters and shot a 38-year-old woman, who remains in a stable condition at the Launceston General Hospital.
"The person who assisted the offender in sourcing the firearm is encouraged to contact detectives, without fear of prosecution.
"It is important we establish the sequence of events which led up to the incident.
"The firearm was imported legally in the 1970s, prior to the Firearms Act 1996, and has never been registered.
"Illegal firearms pose a significant risk to the community, as we have seen with the tragic events of yesterday.
"These events will have a lifelong impact on the families involved."
Information can be provided to Police on 131 444 or anonymously through Crime Stoppers on 1800 333 000 or online at crimestopperstas.com.au
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