When Kim Thien Tran arrived in the UK on the back of a lorry in Milton Keynes in 2017 she was well versed in what to tell immigration authorities: “I’m 16 years old and I’ve been trafficked.”

Tran, then in her late twenties with several children of her own, was treated as a child and put in foster care, as required under a government initiative to support victims of trafficking and slavery, the National Referral Mechanism (NRM).

She soon ran away. Then in March last year Lancashire police carried out raids against a cannabis farm gang. Six members were found in a house in Bootle, Merseyside. One was Tran. Again she told police she was 16 and a trafficking victim. Detectives carried out fingerprint