Counter-terrorism expert Greg Barton has revealed the “missing piece” he says could have helped prevent the Bondi terror attack that claimed 15 lives.

Professor Barton told Sunrise that one of the alleged gunman responsible for the Bondi terror attack was interviewed by officials about extremism in 2019.

Naveed Akram, 24, who along with his father Sajid allegedly carried out the attack, was investigated by the Australian Security Intelligence Organisation (ASIO) in October 2019 when Professor Barton said an “incident response – the counter-terrorism intelligence” was done.

The then 18-year-old Mr Akram was investigated over his association with members of a Sydney-based ISIS terrorist cell, but authorities deemed no further inquiries were needed and the investigation was closed.

“But in the five years since we haven’t had the follow-up work which is sometimes referred to as countering violent extremism,” Professor Barton told Sunrise.

He said the follow-up work allowed ASIO officials to spend time building relationships with people flagged for terrorist suspicions to try to understand what is going on in the person’s life.

The goal was to then try divert the person away from extremism and provide them with support resources, Professor Barton said.

“That seems to be the missing piece we didn’t attend to in the last five years,” he said.

Here is a chronological account of the information available about the alleged gunmen’s movements before the horrific attack.

October 2025: Alleged gunmen filmed ‘training’

In a court statement of facts, police allege a video recorded in late October 2025 depicted the father and son “conducting firearms training in a countryside location, suspected to be in NSW”.

“The accused and his father are seen throughout the video firing shotguns and moving in a tactical manner,” the document reads.

In another video from October mentioned in the court documents, police allege the two men are filmed in front of an image of an ISIS flag making several statements regarding their motivation for the Bondi attack.

“In this video, the accused and S Akram recite their political and religious views and appear to summarise their justification for the Bondi terrorist attack,” the statement reads.

The document states Naveed Akram appears to recite a passage from the Quran, with four long-arm firearms resting on wood panelling behind him.

Also in October, the statement of facts alleges Naveed Akram booked “room 2” in a five-bedroom home on Brighton Ave in Campsie in Sydney’s southwest through Airbnb for a three-week period from December 2 to December 21.

November 2025: Alleged gunmen visit Philippines

The pair travelled to the Philippines in November to receive “military-style training“ according to counter-terrorism officials.

The Philippines Bureau of Immigration said the pair arrived on November 1 and left the country on November 28.

In an interview with news.com.au, Ian Wilson, a lecturer in politics and security, said “from the material available, we know they went to the Southern Philippines which has historically been a site of conflict for a whole range of extremist groups for decades”.

“Now there are micro-splinter factions and a hodgepodge of different groups in Mindanao and a range of different actors broadly networked with (the terrorist group) Islamic State worldwide.

“There are lots of things we don’t know … but you do not go to Mindanao just for the sake of it.”

December 2025: Two days before the attack

New details of what police allege occurred in the lead-up to the mass shooting were revealed in court on Monday.

In a statement of facts prepared by investigators, police say CCTV footage captures two males, alleged to be Naveed and Sajid Akram, the latter who was shot dead by police during the attack, arriving at the carpark near Archer Park, Bondi Beach, about 9.30pm on December 12.

The two males park a vehicle and walk over the same footbridge where the mass shooting unfolded, the documents allege.

“The accused and his father are seen to exit the vehicle and walk along the footbridge, being the same position where they attended two days later and shot at members of the public,” the documents allege.

“Police allege that this is evidence of reconnaissance and planning of a terrorist act.”

It is alleged in the police fact sheet released by the court that the father and son adhered to a religiously motivated extremist ideology linked to ISIS.

December 2025: Day of the attack

The men were allegedly captured on CCTV entering and leaving the Airbnb allegedly booked by Naveed Akram in October.

The pair were allegedly captured carrying “long and bulky” items wrapped in blankets from the property at 2.16am on December 14.

It is alleged the footage then shows the father and son leave on their way to Bondi at 5.09pm.

Originally published as Terror expert reveals ‘missing piece’ that could have spotted Bondi attack