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"He brought out a knife and lunged at me," said Burhan, a teenager who came to the UK seeking safety.

Burhan - not his real name - arrived in the UK in the back of a lorry, aged 16.

But authorities did not believe he was a child and instead placed him into the adult system, where he says he was attacked.

He is one of 137 child asylum seekers - identified by Newsnight - that have been wrongly classified as adults.

Between January 2018 and March 2019, these children were sent into adult accommodation, only for authorities to later accept they had been telling the truth about their age.

Using the Freedom of Information act, Newsnight identified 26 cases in Derby, and 29 in Cardiff. Another nine were identified in Birmingham, 56 in Liverpool, eight in Croydon, seven in Wakefield and two in Glasgow.

These cities are the UK's seven regional hubs for processing asylum seekers.

'I felt powerless'

Burhan - whose identity Newsnight is protecting - is from a troubled area of the Middle East.

"I was in the lorry for three days. I had no food and only a little water, which ran out quickly," he said.

"When I got off the lorry, I went to a petrol station and asked for the police."

Burhan was originally treated as a child, but then social services visited him to say they believed he was in fact 20, not 16.

"I said 'no - you're wrong'," Burhan recalled. "They said if you don't go, we will call the police and the police will take you by force.

"I felt so powerless because no matter how many times I explained to them, they didn't want to believe me."

Classed as an adult asylum seeker, he was sent to live in a room in a house with other asylum seekers, older than him.

It was there, Burhan said, an older man kicked his bedroom door down and attacked him.

"He had a plate in his hand and he smashed it on my head," he said. "My eyesight was blurry and I couldn't see. He brought out a knife… he lunged at me, but I managed to avoid it and ran away.

"I was very scared and I was shivering. I ran away with no clothes on, not even shoes. I only came back after the police had arrested him."

In 2018, almost 3,000 unaccompanied asylum seekers arrived in the UK claiming to be under 18. It's widely accepted that some will be adults posing as children.

Last year, man who posed as a 15-year-old in Ipswich was thought to be as old as 30.

If asylum seekers are deemed to be children, they have more access to education and a better chance of being allowed to settle in the UK.

After eight months, Burhan's case was reviewed by independent social care workers and it was judged that he was a child.

"When they said I was a child, it was mixed feelings. I was happy that finally somebody believed me but I was upset that they wasted my time and they made me feel terrible," Burhan said.

He is now learning English at college and is staying in appropriate accommodation.

Labour Peer and former refugee Lord Dubs told Newsnight that cases such as Burhan's, when the Home Office does not believe someone is a child, are the "harshest".

"This is not helped by the fact that refugees have often been scrutinised by the media for looking older," he added.

"We must not forget that these people have been on terrific journeys, and that they therefore probably look older given what they have endured."

In May, a case was brought before the Court of Appeal and judges ruled the process by which age was assessed was unlawful.

Now, anyone appearing under the age of 25 will be referred to specialist local authority age assessors.

The Home Office said it was "disappointed" by this judgement.

"We take our duty to safeguard and promote the welfare of children in the asylum and immigration system very seriously. However, age assessment is an extremely difficult area of work and is not an exact science," a Home Office spokesman said.

"Our approach seeks to strike an important but sensitive balance between ensuring that children who claim asylum are appropriately supported whilst at the same time maintaining the integrity of the asylum system and preventing adults passing themselves off as children."

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