Thousands of traumatized children in foster care in Britain go missing, with some returning to traffickers who feed them "a web of lies", charities said on Thursday, urging better protection.
UK children's charity Barnado's said on Thursday that 16 percent of children referred to its fostering network had been sexually exploited or abused, and 17 percent were trafficked.
"It is well known that there is a greater risk of trafficked children going missing from care but too often processes are not put in place to protect children," its chief executive Javed Khan said in an email to the Thomson Reuters Foundation.
"Children are threatened, manipulated and controlled by their traffickers who feed them a web of lies leading them to fear authorities," he said, adding that many vanish within days.
More than 50,000 children in England are in foster care, Department of Education statistics show, with thousands disappearing more than once.
Children may abscond because they feel unsafe or isolated, particularly if they do not speak English.
Some contact their traffickers because they fear reprisals against themselves or their families, have been made false promises or believe they have debts to pay, experts say.
Anti-child trafficking organization ECPAT UK said its research showed 28 percent of all trafficked children in care went missing at least once. Vietnamese children were most likely to abscond, often re-enslaved in nail bars or cannabis farms.
More than 150 Vietnamese children rescued from traffickers in Britain have disappeared from care and foster homes since 2015, charities said last month.
Having been in various foster homes from the age of three, British survivor Sarah said she was trafficked for sex at the age of 12 by a gang in England.
"I was alone and vulnerable ... I saw them as people who cared about me," she told the Thomson Reuters Foundation's annual Trust Conference on Wednesday, using a false name.
"For the next seven years I was sold every day to many different men," she said, adding that her school, social services and other authorities failed to see her plight.
Charities have called for specialist foster carers to be trained to look after trafficked children and for the setting up of safe houses with high levels of support and supervision.
"It is vitally important that foster carers are offered the support and training they need to be able to look after highly traumatized young people," said a spokesman for Fostering Network, a charity that supports foster carers in Britain.
At least 13,000 people across the country are estimated by the government to be living in modern slavery but police say that the true figure is likely to be in the tens of thousands.
The government has said it is introducing a scheme to give trafficked children specialist advocates or guardians who could provide support and reduce re-trafficking risks.