In a statement, Queensland police said that Queensland Counter Terrorism Investigative and Intelligence staff have conducted a thorough assessment of the offenders involved to understand the motivation behind such extreme violence and whether there was a further threat to community safety. 

"A full analysis of the evidentiary material indicated the incident was a religiously motivated terrorist attack," said Deputy Commissioner Tracy Linford.

“Specialist teams have analysed an extensive amount of evidential material including diaries, books and notes located at the scene, phone messages, emails, social media posts, witness statements and body-worn camera footage,” Deputy Commissioner Linford said.

On Dec. 12, last year two officers of Queensland police and one civilian were at a Wieambilla property during shootout when police were searching for a missing person. 

According to police deputy commissioner, the  information provides more clarity as to the motivation behind the incident than what was known in the days after the event.

“We now know that the offenders executed a religiously motivated terrorist attack," she said and adding “They were motivated by a Christian extremist ideology and subscribed to the broad Christian fundamentalist belief system known as Pre-Millennialism.

“The attack involved advance planning and preparation against law enforcement.

“There has been no evidence to suggest anyone else was involved in executing the attack in Australia or that there is any ongoing specific threat.” said the commissioner.  

A major investigation into the incident remains ongoing on behalf of the State Coroner.