Queensland police have charged 45 prisoners after a riot at the Capricornia Correctional Centre in October, with further charges expected to be laid in the coming days and weeks.
The alleged offenders were aged between 20 and 41.
The riot, which lasted 16 hours, involved prisoners allegedly accessing landscape gardening equipment and 20 litres of petrol, which was then used to make molotov cocktails.
The prison's chief superintendent Richard Butcher said the riot was the most significant event in the centre's history.
"[Prisoners] were causing significant damage to infrastructure ... they were sniffing petrol, they were threatening staff and prisoners with molotov cocktails," Mr Butcher alleged.
"At the height of the incident, there were about 70 prisoners involved in the indiscipline."
Mr Butcher said eventually the grounds were secured and 40 prisoners remained on the roof of the activities hall.
"We then entered into a negotiation phrase, and slowly but surely those prisoners surrendered themselves, and by 2 o'clock in the morning the last group of prisoners surrendered."
He said the centre lost roughly 180 secure cells and about 150 residential cells at the time of the riot.
"Our response to that is we had to double prisoners up in the available accommodation that we had."
Criminal investigation continues
Acting Detective Inspector Anthony Buxton said it was a "real milestone" to be laying the charges, and anyone found to be guilty of taking part in the unrest faced up to 14 years in prison.
He said police would also be pursuing the defendants to pay for the damage.
Inspector Buxton said the charge at this stage was one of "riotous behaviour", and the investigation took considerable time due to logistics, the size of the forensic evidence, and the large number of alleged offenders involved.
The centre is once again fully operational, apart from one officers' station in the residential area.
Mr Butcher said there had been some procedural changes since the riot and staff had been supported.
Diesel- and petrol-powered garden equipment had also been replaced with electric items.
"All correctional centres did an audit of the security of their garden equipment and their motorised gardening tools, such as lawn mowers, and we made the decision very early on to convert all our petrol or diesel driven garden tools to electric," he said.
As for the cause of the riot, Mr Butcher said an internal investigation was still ongoing.
Those charged are due to appear in the Rockhampton Magistrates Court in July.
Report released
The charges came as the findings of an independent cultural review of the correctional centre were formally released.
The report highlighted some concern around workplace behaviours.
"Inappropriate and unhelpful behaviours, unprofessional conduct and an acceptance and tolerance of inappropriate comments were identified as a theme," it read.
"Concerns were raised about divisions between different sections of the workforce, leading to a lack of trust between different groups.
"Some of the key challenges [in leadership] included a perceived lack of clarity on direction and strategy, a lack of support and a perceived disconnect with staff in frontline roles."
Mr Butcher said since the review started in October, there had been a culture change.
"During my 12-month tenure at the prison, [I] have seen and felt a definite change in the culture for the better."
