The Northern Territory's Correctional Services Commissioner says investigations will commence after a riot at Alice Springs Correctional Centre which saw one officer and two prisoners hospitalised.
National Indigenous Times understands Indigenous prisoners were involved in the incident.
At a press conference on Monday, Commissioner Matthew Varley said at around 9:10pm on Sunday evening a "disturbance" began in the prison's G Block, resulting in clothing and mattresses being set alight.
11 prisoners used a bed frame to ram a dormitory door before breaching a second door, allowing a total of 27 people into a secure courtyard in the incident.
More than 60 officers responded to calls to support the "full complement" of 16 night staff on duty at the time.
Commissioner Varley said staff activated standard emergency response protocols and "chemical agents" helped bring the situation "swiftly under control" by 10:45pm before the incident was formally wrapped up close to 2am.
All prisoners involved were accounted for and underwent decontamination and medical assessment in secure units.
"Quick checks and assessments on our staff indicated that no officers suffered significant injuries. One officer was later taken to a hospital with a bruise and injured knee and some officers suffered minor abrasions bruising through the scuffle," Mr Varley said.
"Two prisoners were later taken to hospital and assessed for minor injuries and lacerations."
Commissioner Varley said a full investigation will take place with the involvement of NT Correctional Services specialised team.
The incident comes after an attempted escape by 15 prisoners from G Block on Boxing Day.
Although being told by officers Sunday night's incident "relates to a cohort of prisoners and difficult behaviours that they've been managing across G Block in the last couple of weeks", he said it wasn't necessarily the same individuals involved in the earlier attempted escape, who are currently under "intensive management plans".
"But whether there are connections and affiliations between groups of prisoners is something that we'll be assessing," Commissioner Varley said.
Commissioner Varley said "sheer brute force" resulted in the breach, conceding "infrastructure and the door locks failed on this occasion", but stated they had not failed in the past and that
"We're going to do an assessment on what else can be done to strengthen those doors," Commissioner Varley said.
"11 men ramming through a door with a bed frame applies a significant amount of force to that door and we'll be working through that as part of our system".
The centre currently holds 680 prisoners - 200 more than originally designed for, however Commissioner Varley says this number is in line with safe capacity determinations and following previous changes and upgrades.
He said "heat and overpopulation are two issues that we're closely paying attention to" and that air conditioning is a considered option going forward, but not the only one.
"We know that prisons are not supposed to be a comfortable place, but at the same time, we have to make sure it's up to the right standards. And that's something we consider all the time," Commissioner Varley said.
High temperatures are believed to be what sparked a 2018 riot at the centre, with the NT ombudsman recommending the installation of air conditioning at the prison last year.
In a statement on Tuesday, the Northern Australia Aboriginal Justice Agency (NAAJA) said "mass incarceration of Aboriginal people in over-crowded, hot prisons" is the 'real story' undermining the Territory's justice system, and leading to the riot.
NT Deputy Chief Minister, Attorney General and Minister for Justice and Aboriginal Affairs and Treaty, Chansey Paech, said agreed there is a gross over-representation of Aboriginal people in NT prisons and youth detention centres".
"Our Government is supporting a new model of delivery towards reducing reoffending and imprisonment rates of Aboriginal Territorians; engaging and supporting Aboriginal leadership; and improving justice responses and services to Aboriginal Territorians," Minister Paech told National Indigenous Times.
Commissioner Varley said prisoner lockdowns are used at the centre on a case-by-case basis, but he had "no information to suggest that lockdowns are precipitated to yesterday's (Sunday's) event".
He said the separation of inmates on remand and those serving custodial sentences would be something needed to be considered "in the context of our existing infrastructure".