The crisis surrounding the treatment of WA’s unwanted children has deepened with revelations authorities are using the State’s only juvenile jail to hold them because they cannot find a place for them to stay.

The West Australian has learnt two wards of the State remain locked up at Banksia Hill Detention Centre because there are no vacancies at any residential or community care homes in WA.

The Department of Justice confirmed the children, who are the responsibility of the Department of Child Protection, have been detained in the facility because of a lack of suitable accommodation but the department would not reveal their ages or how long they have been locked up for.

A spokeswoman would also not say why they had been held.

She also confirmed authorities used Banksia Hill to hold children when all other avenues to find suitable accommodation had been exhausted.

“Where efforts to provide other options to young people are exhausted, young people who are arrested, on remand or sentenced, can be held at Banksia Hill Detention Centre,” she said.

The alarming admission comes after The West Australian revealed last week how child welfare officials were prepared to let a 10-year-old boy be locked up because they could not find a place to take him.

The details emerged during a hearing at Karratha Children’s Court but Magistrate Elaine Campione refused to send the boy to the detention centre, saying it was not a suitable place for a child in his situation.

She told the department it was its responsibility to find accommodation — not the justice system’s. In response to the story, Child Protection Minister Simone McGurk ordered a full briefing into the incident saying she was “very concerned” officials in her department were willing to let the boy be sent to Banksia Hill.

But Greens MLC Alison Xamon said this was not enough in light of confirmation two children were currently being held in detention, adding it was also a breach of the intent of the Young Offenders Act.

“This situation is completely unacceptable,” she said.

“A court has said these children are better off outside but they have been left languishing. Prison is a terrible place for children.

It should always be used as a last resort.”

Since 2014, 16 children aged 10 have been held at Banksia Hill on a range of charges, including assault and robbery, for an average stay of four days, according to Department of Justice figures.