A quarter of migrants who pretended to be children after crossing the English Channel from France were over 18, council figures revealed.
Of the 1,668 who told officials they were children after landing on the Kent coast in the past five years, more than 400 have subsequently turned out to be adults.
A source from Kent County Council told the Sunday Telegraph: “Following the age assessment, around 25% are considered to be 18 years of age or older. They will then almost definitely appeal that to the courts and the board will pay all legal fees.
Last week, Abdulfatah Hamdallah was stranded dead on a beach in Sangatte, near Dunkirk. His friend, who is said to be 16, managed to swim ashore and initially reported that he believed Hamdallah was the same age as him. Hamdallah was 28 years old.
Border Force officers aboard HMC Hunter talk to migrants aboard an inflatable boat in the English Channel on August 10
Hamdallah was from the West Kordofan state in Sudan, which borders the war-ravaged areas of Darfur and the Nuba Mountains.
Traffickers in the country are using Facebook to advertise their services, telling their followers “now is the best time to get on the boat.”
A total of 4,999 migrants, mostly men from North Africa and the Middle East, have made the treacherous journey across the Channel so far this year.
Kent has started transferring the newcomers to other councils across the country as he can’t keep up with the numbers, the Telegraph reported.
On August 14, the local authority said it had reached capacity to accommodate unaccompanied asylum-seeking children and could no longer accept any.
Mr Hamdallah (pictured) could not swim and drowned when their boat burst a mile from Sandgatte beach
Kent cares for over 600 children under the age of 18 who cost taxpayers £ 200,000 a month.
950 other people, aged 18 to 25, were temporarily accommodated.
Children under 18 will be entitled to financial assistance for accommodation up to the age of 25.
Those found to be adults will be returned to their country of origin, a process of about three years that is fraught with legal pitfalls.
Migrant men taken in by British border forces arrive at the port of Dover on August 20
Refugee rights organizations say age assessments are unscientific and make mistakes.
Kent Refugee Action Network told The Telegraph: “Age ratings are imprecise, subjective and arbitrary.
“In fact, the problem is not people claiming to be younger than they are, it’s age ratings that often place them as older than they are, and this has devastating consequences, leading children placed in foster care to be transferred to adult accommodation. “