A group of neighbours stood huddled in the next-door driveway on Friday afternoon as police in coveralls ferried items in and out of the trailer set up on the narrow street.
Items belonging to Mr Abdi were found in the home, Deputy Commissioner Tracy Linford believed.
Police Commissioner Katarina Carroll described the double homicide as an act of terrorism.
Mr Abdi’s father, Mohammad, said he was saddened by dashcam footage taken in the minutes leading up to the “trigger happy” police shooting.
The footage appeared to show Mr Abdi walking backwards along the highway, with police officers in front. Police claimed he was provoking them.
“My son needed help when he was there [on the motorway], and the help he got was to get shot, and that’s very sad,” he said.
He said his son was a peaceful person who never appeared to be radicalised but had been “looking at his identity”, with concerns around his mental health brushed off by police.
“[He was] a young man who wanted to actually have a limitless life – as any young person in Australia – who couldn’t take a job as it comes, who couldn’t actually go and play soccer because there is a tracking device on his leg, who is stigmatised because of the identity he was given. I felt he was under mental pressure.”
Family spokesman Ali Kadri said the young man had showed promise, and had previously helped him deliver cards to the Christian community at Christmas.
“Instead of providing him help, the system has failed him,” Mr Kadri said.
While he said it was heartbreaking to hear of the elderly couple’s deaths, he had concerns about the way police were linking the incidents.
“The concern we have with the terror connection to homicide is terrorism is defined as politically motivated violence. Linking the deaths of this elderly couple to terrorism is premature, especially in the absence of any solid evidence in [the] public domain,” he said.
Mr Kadri said Mr Abdi was not being investigated, and had not been charged, over anything terrorism related at the time of his death, and he called for more details from police on why they were describing it as an act of terrorism.
Mr Kadri said a “thorough and independent” investigation needed to take place into the shooting, particularly following the police shooting of Afghan man Mohammad Ikraam Bahram, 24, in the CBD in January.
“Let this incident be a trigger for a better, more united society, and not that of more division, hate and marginalisation,” Mr Kadri said.
Shane Satterley, a Griffith University PhD candidate in Islamist extremism in Australia, said the mental health issues reportedly suffered by both Mr Bahram and Mr Abdi did not “necessarily explain why they turned to violence, if a terrorist motive is to be found”.
“Both fit the profile of a jihadist: male, early 20s and Afghan and Somali backgrounds,” he said.
“However, more needs to be established as to what links to the jihadist ideology or social support networks actually existed before we jump to conclusions.
“[Mr Bahram’s] attack fits the jihadist tactic of high exposure, being intentionally violent, and public,” he said. “However, no known links to jihadism have been established as yet.
“For Abdi, links to terrorism have been established, but the incident to which he has been most recently linked does not appear to be what an ISIS propagandist would consider great for mass appeal or recruitment.”
Jocelyn Garcia is a journalist at the Brisbane Times, covering breaking news.
Matt Dennien is a reporter with Brisbane Times.
Toby Crockford is a breaking news reporter at the Brisbane Times