Bletchley Park boffin's daughter was a slave -

One of the three women allegedly held as a slave by a Maoist sect was the daughter of a Second World War codebreaker.

Josephine Herivel is the daughter of John Herivel, one of the leading code breakers at Bletchley Park who deciphered the Enigma code.

Slavery suspect Aravindan Balakrishnan and his wife Chanda were arrested in Brixton, south London, after Herivel raised the alarm. They have been charged with slavery related offences.

John Herivel appears to have given up admitting the existence of Josephine and when he died in 2011 his obituaries only made mention of his two other daughters Mary and Susan.

Josephine joined Balakrishnan's extremist collective in the 1970s after moving to London to study.

Family friend Frances Presley told the Herald Scotland that attempts by her family to make contact failed.

She said that John and the family tried to contact her for years but she had cut herself off from them.

Josephine was prosecuted in 1978 when police raided the group's south London bookshop and headquarters. She and five fellow cult members appeared in court charged with obstructing police officers.

She dubbed the judge a "Fascist lackey" which probably did not help her case much. Herivel was also with the sect when one of its members, Sian Davies died after falling from a bathroom window at a house in south London where the collective were living.

Herivel lived with the group for more than 30 years before contacting the Freedom Charity and reporting that she and two other women were being held against their will.