The federal government is expected to consider law reforms to stop violent extremism at the source following the fatal shooting of two police officers and a civilian on a property in rural Queensland.
Members of the Train family - former school principal Nathaniel Train, his brother Gareth and sister-in-law Stacey - gunned down two officers who visited their property to investigate a missing person report on Monday.
Constables Matthew Arnold and Rachel McCrow were killed along with neighbour Alan Dare, who was shot in the back when he went to the property to assist.
Queensland Police are looking into the Train brothers' online activities, including their possible involvement in extremist conspiracy groups and forums.
Labor MP Peter Khalil, who chairs federal parliament's intelligence and security committee, told AAP that Australia needed a society-wide approach to counter extremism.
He said national security agencies were being challenged by the increasing pathways to radicalisation made possible by "online echo chambers" and the federal government was prioritising cyber-security strategies and counter-terrorism law reform.
"The pipeline towards extremism needs disrupting at its source not just at the pointy end of the spear where violent attacks are imminent," he said.
"By anticipating the increased raft of national security challenges ... we can take decisive action and counter-measures to improve our resilience."
The head of the Australian Security Intelligence Organisation (ASIO) Mike Burgess expressed concerns with the rise of online radicalisation in February.
Mr Khalil said ASIO had reported ideologically motivated violent extremism made up around half their onshore caseload.
Opposition Leader Peter Dutton urged friends and families of people falling down conspiratorial rabbit holes to proactively contact authorities before tragedy strikes.
"There are some sick individuals out there and the internet's made it possible for them to spread their lies and their hatred, and so it is difficult for authorities to pick that up," Mr Dutton told Nine Radio.
"The parallel obviously is with young people who are being indoctrinated online ... they spend hours and hours and hours reading this information and information is deliberately posted, knowing that will influence people in a negative way."
Mr Dutton doubled down on his criticism of encrypted messaging services, although the Train family posted in forums rather than via the secure software.
Attorney-General Mark Dreyfus said the Queensland police force should be allowed to complete its investigation without speculation or interference.
"Right now, three families are grieving and the Queensland Police are conducting an investigation into these horrific murders," he told reporters in Canberra.
He said federal national security and police agencies were ready to assist with all investigations on the matter.
