Tensions remain high in the youth wing of a West Australian prison after six guards were allegedly injured during a riot and inmates freed themselves from their cells.

Casuarina Prison’s youth custodial officers feel unsafe following the incident on Saturday when a guard’s keys were allegedly stolen and she was hit with a makeshift weapon.

“There is concern about the escalation targeting (officers) to access their keys,” Melanie Bray, Community and Public Sector Union assistant secretary, told reporters on Monday.

“It’s very, very, very unusual … It’s a significant concern.”

Ms Bray, who spoke outside the maximum-security prison after meeting with guards involved in the “major disturbance” said the youth wing had been ripped apart.

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“There is nothing pretty about that unit … It’s not like it’s sort of returned to a harmonious normal,” she said.

“They haven’t sort of gone back to everybody’s lull and everybody’s quiet, it’s still an escalated environment.”

She said some of the officers involved in the incident regularly faced violent juvenile inmates.

“This might be their third or fourth traumatic incident over the last two weeks,” she said.

“It’s not a thing that happened on Saturday for our membership, it’s a thing that still happening.

“That’s not a working environment anybody wants to be in.”

Ms Bray said a female officer assaulted with a metal object had been hit with either a pole or a plate and she had been released from hospital.

“As I understand it, there is some weakness in the facility where somebody might be able to turn some of the infrastructure into a weapon,” she said.

Two inmates allegedly stole the keys to the prison’s accommodation areas about 4pm and freed 11 others from their cells before climbing onto the roof and damaging property.

A total of six guards were injured during the unrest, debris was thrown at staff, and three buildings were damaged and one flooded before the incident ended about 2.15am on Sunday.

The WA government has faced significant criticism for detaining juveniles as the adult prison amid continued unrest at the Banksia Hill Juvenile Detention Centre.

Premier Mark McGowan on Sunday said the unrest during supervised recreation time was appalling and shocking and those involved would face charges.

Ms Bray said staff had also previously raised concerns about youths being detained at Casuarina, which is primarily a prison for adult men.

She also said Casuarina’s youth wing was not fully staffed on Saturday and called for the government to listen to officers.

“When they come to the table and say ‘we think we have some solutions and we need you to listen’ the very least you do is listen”, she said.

The Justice Reform Initiative said the incident showed the danger of justice policies that rely on incarceration and fail to address the cause.

“Everybody deserves to be safe at work, however, we need to take a clear-eyed look at what is happening here for children who are imprisoned,” executive director Mindy Sotiri said.

“This unacceptable behaviour does not emerge from a vacuum. We need to understand the context in which it is occurring.”

Dr Sotiri said locking up children, who often have disabilities, in punitive prison conditions makes it more likely they will reoffend when released.

“Jailing is failing these children, it is failing the people who are paid to supervise them, and it is failing all West Australians,” she said.

-AAP