An Indigenous teenage inmate has been rushed to hospital in critical condition following a serious incident at Casuarina Prison in Perth.
WA Premier Roger Cook said the 16-year-old boy was found unresponsive at Unit 18 at the adult prison about 2am today.
"We have limited information to tell you at this point in time," he told reporters.
Corrective Services Minister Paul Papalia said the teen had contacted the control room, alerting officers to an incident, before he was found.
"I can confirm that what happened last night, the boy had contacted officers via the intercom, it was only a matter of minutes later that he was found unresponsive," he said.
"Officers commenced resuscitation and they were able to regain a pulse.
"They have done an outstanding job.
"We are thinking about the boy and hope his condition improves."
Papalia praised corrective officers for their quick response to what he described as a "sensitive situation".
"This is a young person in detention, it's all going to be subject to an inquiry," he said.
"I just want to reiterate (staff) have done an extraordinary job in a tough situation."
WA's Department of Justice said staff worked to save the teen after he was found.
"Staff commenced resuscitation before the arrival of three paramedic teams," the DOJ said in a statement.
"The Aboriginal teenager remains under medical care at Sir Charles Gairdner Hospital in a critical but stable condition.
"All circumstances surrounding the incident are being investigated.
"Detainees and staff at Unit 18 and Banksia Hill Detention Centre will be provided counselling and support."
Unit 18 was initially established as a temporary facility to accommodate high-risk youth detainees at Casuarina's adult prison.
The state's only youth detention centre, Banksia Hill, also holds juvenile inmates but the cohort was split last year.
Both the unit and Banksia Hill have been subject to long-running criticism over living conditions, safety concerns and the treatment of inmates.
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