A woman who died after falling from a window had been living with the London 'slavery' suspects, it has emerged.
The cousin of Sian Davies said she had died after in 1997 after mysteriously falling out of a bathroom window in the house the group were living in in Herne Hill, south London.
Ms Davies was kept in hospital for seven months after the fall, but her family claim they were not told.
The Mirror is reporting that the death is being investigated by police, as they try to unravel what happened in the house run by Aravindan Balakrishnan and his wife Chanda in Brixton, where three women say they were kept as slaves.
Police have confirmed that there are ongoing inquiries relating to a total of 13 addresses, all in London, linked to the couple, who ran a communist cult in the 1970s.
Sian Davies had reportedly lived there for 20 years.
Her cousin, Eleri Morgan, said Aravindan Balakrishnan was more of a "toothless old man" than a "charismatic" figure.
She said Ms Davies wrote home talking of how she was looking after the "mothers of the world" but was not allowed to see her cousin.
Her letters always spoke of "comrade Bala" - the name that Balakrishnan was referred to.
Morgan met Balakrishnan at the inquest into her cousin's death. She told ITV News: "I had such a shock because I imagined somebody charismatic and there was this toothless old man - well looked old."
A senior council source confirmed that Balakrishnan and his wife Chanda were arrested last week by police amid allegations that they held three women for more than 30 years. It is claimed they were leaders of an extremist Maoist collective.
The alleged victims - a 30-year-old Briton, a 57-year-old Irishwoman and a 69-year-old Malaysian - are believed to have suffered years of "physical and mental abuse" at the hands of the pair.
The youngest of the three alleged victims is said to have written letters to neighbour Marius Feneck, 26, describing her life as being "like a fly trapped in a spider's web".
The woman wrote more than 500 letters to him in seven years, the Guardian said, after becoming infatuated with him.
One letter apparently told of the "unspeakable torment" she suffered behind locked doors and windows, and of how she was terrified that her captors - "these evil criminals... who dare to call themselves 'my relatives'" - might do something to him.
Knows as Rosie, she also knitted a jumper for another neighbour, Jesse Paddy.
House-to-house inquiries have been carried out in Peckford Place in Brixton where the three women were found.
The couple, aged 73 and 67, are believed to have been well-known to the police in the 1970s after setting up a communist squat, the Mao Zedong Memorial Centre, in Acre Lane, Brixton in 1976.
Morgan recalled that her cousin had a boyfriend called Martin. She told ITV News: "She was outgoing, we went clubbing in our younger days, enjoyed the good life, and next time I saw her she was in the morgue...
"I picked up the paper and oh my God, Bala and it all came back to me...In the paper it implied they were all foreign students, but earlier they weren't all foreign. I know of Martin and Sian - what he did to our family he did to others."
Balakrishnan was a former member of the national executive committee of the Communist party of England (Marxist-Leninist) but documents show he was suspended from the party in 1974 for pursuing "conspiratorial and splittist activities".
Documents also show how in 1978 police raided the Mao Zedong Memorial Centre, arresting 14 members of the organisation, including Aravindan Balakrishnan and wife Chanda, referred to as Comrade Chanda.
A source at Lambeth Council said the couple were believed to have been in the property for around 10 years after moving there from a council property, and concerns had previously been raised with police about the education of the youngest woman.
Scotland Yard would not comment on the claims, but previously said two of the victims met the male suspect through a "shared political ideology", living with him at an address that was effectively called a "collective".
The case came to light after the Irishwoman rang the Freedom Charity last month to say she had been held against her will.
The couple, who are of Indian and Tanzanian origin and came to the UK in the 1960s, have now been released on bail until a date in January.
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