Queensland police are treating a double murder and a police shooting on a busy motorway in Brisbane's south as a terrorism event and have warned people to check on their relatives in the area.
Raghe Abdi, 22, threatened police with a knife before being shot on the Logan Motorway on Thursday morning.
Abdi had been influenced by Islamic State, was on bail and had previously been arrested by counterterrorism officers.
Police say the shooting is directly linked to the deaths of a 87-year-old man and an 86-year-old woman, whose bodies were found with significant injuries in a home in Parkinson on Thursday afternoon.
Queensland Police Deputy Commissioner Tracy Linford says both incidents are linked because Abdi's property was found at the couple's home, and that items belonging to them were also found on Abdi.
She says the incidents are no longer purely criminal matters, but are being treated as terrorism.
"As a consequence of this investigation, and what we have now gleaned to date, we are treating this matter as a terrorism event," she told reporters.
"And I want to stress that nothing else has been uncovered at this point in time that would indicate that there are any other persons involved in this terrorism event."
Commissioner Linford said the events had been reclassified as a terrorist incident due to Abdi's history, because the shooting indicating he wanted to harm police, and as a result of his links to the double murder.
"When you put all those things together I think it's pretty clear that we need to treat this as a terrorism event, and as such, we'll make sure that we've had that lens over what would normally be a homicide investigation," she said.
Police have been door-knocking in Parkison, where Abdi removed his GPS tracking device, to find any further witnesses to Thursday's events.
Officers are also concerned about the welfare of people living in the area after the discovery of the elderly couple's bodies.
"Can I ask anybody who's watching today or listening to your news - If you have family living in that Parkinson area it would be a good time to check in on them and make sure that they're okay," Commissioner Linford said.
The AFP suspect he had been influenced by IS and he was arrested on suspicion of an attempted foreign incursion when trying to depart Brisbane Airport for Somalia in May 2019.
He was released without charge due to insufficient evidence but had his passport cancelled.
In June 2019, he was charged with further offences including refusing to give the passcode for his phone.
He was remanded in custody after refusing to answer the magistrate or acknowledge the authority of the court, before being granted bail in September 2020.
Australian Federal Police Deputy Commissioner Ian McCartney said before Thursday's incident there were no indications there would be an escalation of violence or that Abdi posed any harm to the community.
"Certainly, up until this point, the information that we had was that his focus had been primarily focused in terms of offshore, an offshore threat as opposed to an onshore threat."
The Ethical Standards Command is investigating the shooting with oversight by the Crime and Corruption Commission.
