A major riot has broken out at the detention centre on Australia's Christmas Island overnight, the rampage resembling "a warzone", according to one human rights advocate.
Iwi N Aus co-founder Filipa Payne, who campaigns for the rights of expat New Zealanders in Australian detention, says all but one compound was set ablaze during the riot on Saturday night.
She says the number of those involved is unknown at this stage, but it's understood the majority of the men participated in the unrest.
Tear gas was deployed to quell the detainees, Payne said, leading to one man's lung collapsing.
"This is absolutely appalling, what happened last night. It's a disgrace for not only Australia but a disgrace for New Zealand that we've allowed these people to continue to be treated with such brutality," an emotional Payne told Newshub on Sunday morning.
"It was a warzone last night - there were fires everywhere."
It marks the second spell of violent unrest in the facility this week. On Tuesday, tensions flared when detainees took to the roof and set fire to mattresses in protest.
Kiwi inmate Ace Salu told Newshub the men are locked inside their "chicken houses" for 22 hours a day.
"The standard of living here - it's terrible. We have tried everything peacefully to ask them for all the necessities we need."
Detainees allege the facility's standard of living is tantamount to torture, with a severe lack of medical care, inadequate access to treatment and almost total isolation from their families.
"Ever since Christmas Island has reopened, there have been no classes or stimulation for these men. They've been locked down for 22 hours a day, and only get physical activity for two hours a day outside of their compound," Payne said.
"They've been asking and pleading for cooking classes, music classes, stimulation - something, anything - for the people to know they are actually cared about. They haven't received anything."
She is urging the New Zealand Government to intervene, claiming if China or Japan were responsible for the alleged mistreatment, officials wouldn't hesitate to act.
"This is our responsibility - It's time for New Zealand to sit human lives ahead of trade," she said.
"We have to stand up and be accountable for the behaviour that Australia - and the brutality that Australia - is taking on people. We can't just sit beside it and allow it anymore.
"Please New Zealand, it's time to stand up and do something."
Payne understands people are now being held in separate parts of the facility and are waiting to be guided out by authorities to receive treatment for any injuries sustained in the fracas.
The Christmas Island Immigration Detention Centre is the Australian government's holding pen for refugees and foreigners awaiting deportation - however, many don't get out for years.
Following the first bout of unrest this week, Newshub obtained letters sent from Christmas Island detainees to advocates on the outside. In the correspondence, the men claim they receive little medical care, including no dental or mental health services.
One has been begging for antibiotics to help his tooth pain, while many others say they are suffering from depression.
New Zealanders imprisoned at the facility say they've already done their time.
"You are gonna look at us and think we're just criminals, but please have a heart, show some compassion," Salu said.
Australia's mass deportation regime was halted in March amid the ongoing COVID-19 pandemic. Although expulsions from the country have gradually resumed, numerous detained New Zealanders continue to live in limbo.
Earlier this week, Newshub asked Australian Border Force when deportations to New Zealand would resume, but they didn't respond.
If you have any information, please email Shannon Redstall on shannonredstall@newshub.co.nz.