Police will probe possible links between a gun seized in South Australia and three bikie gang-related shootings that took place within hours in March.
It comes as police confirmed ongoing friction between the Rebels and Comancheros in the ACT as more outlaw motorcycle groups tried to set up shop in the territory.
Canberra was rocked by a string of brazen shootings earlier this year, with shots fired at homes in Kambah, Stirling and Florey overnight on March 12 and 13.
A man, 36, was injured in the Stirling incident.
The night of violence followed five shootings within 10 days in February.
Police revealed on Monday there had been major developments in their probe into the March incidents.
Officers received information that a person in South Australia might have information about the shootings they were willing to share, ACT Policing said.
Police from the anti-gang Taskforce Nemesis travelled to Adelaide to speak with the person and seized a handgun and numerous rounds of ammunition.
Detective Senior Constable Paul Reynolds said there hadn't been any charges laid in the ACT in relation to that firearm.
He said there was another person before South Australia's courts on charges linked to the gun and "as such it would not be prudent for me to comment further".
The guns and ammunition were brought back to the ACT and were undergoing forensic and ballistic tests.
Police will investigate any links between the firearm and the March incidents.
Detective Senior Constable Reynolds said the gun was the second weapon seized in relation to the shootings.
A Ngunnawal man, 22, and a woman, 23, are before the courts after police allegedly found a sawn-off shotgun and ammunition when they searched the woman's home in April.
Police have also called for the public's help to identify three people they believe could help them with their investigation.
The first man was described as being of Pacific Islander/Maori appearance with a heavy build.
The second man is described as of Caucasian appearance with a skinny build and dark hair, and the woman of Caucasian appearance with bleached blonde hair.
Detective Senior Constable Reynolds said police still believed outlaw motorcycle gangs were behind the violence.
He said police had received a "high level of support" from members of the community who had come forward with information in the wake of the shootings.
"That's indicative of the community's response to these sorts of incidents," he said.
"They feel strongly about this, they don't condone these overt acts of violence and they're willing to assist us in any way they can."
He said any comment on whether tensions were likely to flare again would be purely speculative but police would continue to investigate all bikie gang-related crime under Taskforce Nemesis.
Detective Senior Constable Reynolds said historically the Rebels were the only bikie gang in the ACT, but a newly-established Comancheros chapter had "created some friction" between the two groups.
"We do have information that more outlaw motorcycle gangs are looking to establish a presence in the ACT, and that's something we'll be actively looking to combat with the introduction of anti-consorting legislation."
Canberra's police chief Rudi Lammers in February welcomed anti-consorting laws proposed for the ACT that would give officers greater powers to clamp down on escalating bikie gang activity.
But plans for tougher legislation were criticised by civil libertarians and law groups, who cautioned against a knee-jerk reaction that could erode human rights.
Anyone with information to Crime Stoppers, 1800 333 000 or act.crimestoppers.com.au.