Refugee children are being used as an easy target to boost deportations as the political parties vie to be seen as tough on asylum, charities have warned.

Organisations working with refugees are bracing themselves for more deportations as Labour and the Conservatives promise tougher asylum policies. Their warning comes as a Portsmouth school continues its fight to keep one of its pupils.

Snapshot statistics from the Home Office show the number of children detained in removal centres on a given day rose from 10 to 60 over six months, while the overall number of failed asylum-seekers removed fell by 13 per cent.

Bill Bolloten, a refugee education consultant, said: “There is a political culture to see who can be toughest on asylum. Teachers and others who work with children see the human consequences.”

The Institute of Race Relations and the National Council of Anti-Deportation Campaigns report a rising number of calls from teachers worried about pupils facing deportation. In some cases pupils have been arrested at school.

In Kent, the director of social services has asked all schools not to let immigration officials on to the premises without permission. Many initial decisions to refuse asylum have proved wrong, they said, with figures showing about a fifth of first appeals succeed.

Concerns have been heightened by Home Office guidance, which authorises the use of control and restraint techniques on those children fighting deportation in rare cases where the safety of the child or another person would otherwise be endangered.

The deportation of a pupil can have a devastating impact on a school, Mr Bolloten said. “Schools are protesting at the unfairness of asylum policy and the harsh way it impacts on classmates,” he said.

More than 150 pupils, teachers and parents gathered outside Portsmouth Guildhall on Saturday in the latest of a growing number of campaigns by schools to help pupils threatened with deportation.

Lorin Sulaiman, a 15-year-old refugee at Mayfield school, arrived in Britain from Syria a year ago unable to speak English. Her father had disappeared after being arrested for campaigning for human rights for the Kurds. She is now on the gifted and talented register and hopes to become a doctor.

But Lorin, along with her mother, Amina Ibrahim, whose surname she sometimes uses, and her 16-year-old sister, Eva, was arrested and detained last October until her school secured her release.

Derek Trimmer, headteacher, said: “One moment she’s incredibly excited to be back with her two best friends, but in another month she could be separated from them.

“There have been times when she’s not slept at night, and I dread to think how her best mates will cope if the catastrophe of her being shipped out happens.”

The family have been given until the end of February while the case is reconsidered.

A Home Office spokesman denied there was a policy to deliberately target families with children, but said it was vital for the integrity of the asylum process that failed applicants be deported, if they did not leave voluntarily.

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