A vulnerable 15-year-old boy who needed to move into secure accommodation had to be taken to Scotland because no suitable unit could be found in England or Wales, a judge has heard.

Deputy High Court judge Leslie Samuels approved the move to Scotland after being told council staff responsible for his welfare had contacted more than 100 providers of specialist accommodation in England and Wales without success.

The judge heard the boy, from London and who did not know where Scotland is, had recently arrived at the unit after an “uncomfortable” 11-hour journey.

He said the case is the latest to highlight the lack of “regulated placements” in England and Wales for “troubled young people”.

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Judge Samuels considered the boy’s case in recent hearings at the Family Division of the High Court and outlined detail in a written ruling published online.

The judge said the boy could not be identified in media reports of the case.

He said the youngster is “vulnerable and troubled” and has been in council care for three years.

The boy had been living at a placement in London which been unable to “contain” him or keep him safe, said the judge.

He had become involved with gangs, been arrested for carrying a “bladed article and assault”, and been stabbed.

Social services bosses concluded he needed to be in secure accommodation.

“It was clear that staff at (his) current placement could no longer keep him safe,” said the judge. “He was at an immediate risk of significant harm or death.”

The judge said the council involved had shown him a “chronology of inquiries” to find a suitable unit.

“It details a request sent to more than 100 providers in England and Wales to identify a placement,” said the judge.

“Not a single placement was identified that was able or willing to offer (him) a place.

“It was only when the search was extended to Scotland that a placement could be identified.”

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Sir James Munby, then the most senior family court judge in England and Wales, raised concern about the shortage of secure units nearly five years ago, and many other judges have raised concerns since then.

Earlier this year, Mr Justice MacDonald said a lack of suitable units had left him with no choice but to authorise a suicidal teenager’s placement in “sub-optimal” emergency accommodation.

Mr Justice MacDonald said in February that the 16-year-old girl was “highly troubled and vulnerable” and at high risk of self-harm or suicide.

But he said nearly six months after a council had made an application, and after 11 hearings in the Family Division of the High Court, there was still no suitable care placement available.