The man who carried out the terror attack in an Auckland supermarket fixated on and became obsessed with a person involved in his management after he was released from prison.
The Herald has learned that it was a fixation that grew during Ahamed Adil Mohamed Samsudeen's weeks of freedom before his death and was unrelated to his extreme, Isis-seeded beliefs.
The person who was subject to Samsudeen's growing obsession alerted police to increasing and unwelcome contact, the Herald was told.
The Herald has chosen not to name the individual after being told of potential security concerns. Police has said Samsudeen acted alone.
The individual has been approached for comment and declined to make any statement.
On Friday, Samsudeen was in Countdown supermarket in Auckland's New Lynn when he followed through on years of threats to carry out an attack in the name of Isis. Samsudeen took a carving knife from the shelf and injured seven people with it before being shot dead.
The officers who shot him were part of a specialist team of 30 people who had spent the previous 53 days since his release carrying out surveillance on Samsudeen. Among those people were armed police from its Special Tactics Group.
The team assigned to follow Samsudeen had been briefed on his growing obsession with the individual. It was considered an escalation of Samsudeen's aberrant behaviour and ramped up concern he was losing control.
The briefing came after the individual went to police with concerns over Samsudeen's behaviour, which centred on attempting to make contact and communicate.
The police asked the individual to make a formal complaint of harassment so Samsudeen could be arrested. The Herald was told no complaint had been lodged by the time the attack happened.
Instead, the target of Samsudeen's obsession urged police to get an assessment of his mental health. One aspect considered to have hamstrung authorities was a mental health assessment needed a face-to-face meeting, which was extremely difficult during the Covid-19 lockdown.
By the time the attack took place, the individual had created significant professional distance from Samsudeen in an effort to dissuade his interest.
A police spokeswoman said "if information was received that indicated the terrorist may have committed any offences, that would have been subject to investigation as far as possible".
The spokeswoman said police were not investigating any complaints at the time the attack happened and had no evidence that would have supported charges against Samsudeen.
A psychological assessment was part of his supervision conditions when released from jail, she said, although responsibility for that rested with Corrections.
Corrections had yet to make any statement on whether the psychological assessment was done.
Intelligence analyst Dr Paul Buchanan of 36th Parallel Assessments said Samsudeen would have emerged from prison in July into a world absent the reinforcement he had found in online engagement with Isis and its propaganda materials.
"He's thrown into a vacuum," said Buchanan, with Isis having collapsed since its peak and years having passed without being exposed to its indoctrination.
He said the lack of "effective relationships" likely saw his "emotional resources" directed towards this individual "in the absence of any other effective thing that compels him".
"Is this obsessive focus displacement from his initial love (for Islamic State)?"
Of the seven injured, four people remain in hospital following the attack. Police said all were in a stable condition. Three were in an intensive care unit with one of those expected to move to a ward today.
The Chief Coroner, Judge Deborah Marshall, has now taken charge of the inquiry into Samsudeen's death.
At this stage, there has been no announcement of any other inquiry into the New Lynn attacks. Prime Minister Jacinda Ardern had repeatedly assured the public that all possible steps had been taken to stop the attack.
Samsudeen had spent almost four years in prison either while sentenced on previous charges or awaiting fresh charges. His refugee status had been removed and there were efforts underway to deport him after a 2018 ruling which was subject to an appeal that had yet to be heard.
His entire engagement with the criminal system centred on his Isis-fuelled obsession, including collecting and watching its violent recruitment material online or repeatedly attempting to buy a large hunting knife.
Police and officers from the NZ Security Intelligence Service had investigated and monitored Samsudeen since 2016, around the time Isis was approaching its peak power across the Middle East.