The couple accused of holding three women as domestic slaves in south London for 30 years had been leading lights in a cultlike far-left political group which worshipped the Chinese revolutionary Mao Zedong and believed that their area of south London was on the verge of being liberated by China's Red Army.

Aravindan Balakrishnan, 73, named for the first time on Monday, was a senior member of the tiny Communist party of England (Marxist-Leninist) in the early 1970s, before splitting away in 1974 to form an even more niche and hardline grouping, the Workers' Institute of Marxism-Leninism-Mao Zedong Thought.

His 67-year-old wife, Chanda, was part of the same grouping, which set itself up in 1976 in a library-cum-commune inside a large Victorian building in Brixton, south London, with about 25 members. Its leader, Balakrishnan, was known at the time as Comrade Bala.

Steve Rayner, an academic who studied the group, noted its cultlike attributes, in which there was little debate and the few members with jobs donated all their income to the organisation. Rayner, a professor at Oxford University, who studied Balakrishnan's group for a 1979 PhD thesis on leftwing groups, described the leader's "superior ability to manipulate" other members, who were mainly from overseas and appeared vulnerable.

Rayner's investigation found that members, who wore Mao badges at all times, believed that they and the rest of Brixton would soon be liberated by the Red Army. He said the group was the "clearest case of far-left millenarianism which I have encountered".

The couple were both arrested on suspicion of holding three women captive at a series of addresses in south London including, most recently, a council-owned flat in Peckford Place, Brixton. Police inquiries have since tied the group to more than a dozen properties around south London over the decades.

Police sources indicated that they were investigating claims that a woman fell to her death from a window at one of these addresses in 1997. A neighbour of the Victorian property in Herne Hill, south of Brixton, where the group are believed to have lived for about seven years from 1997, said the household was known locally as "something to do with a cult". Kate Roncoroni, 43, whose house backs on to the road, said: "I came here in 1996. It could have been within two years of moving in. All I remember was there was local gossip that this woman had fallen out of a window and that she had died."

A Metropolitan police spokesman said: "We are aware of this and we are attempting to access archived paper records from the inquest."

A cousin of the dead woman, who was named as Sian Davies, 44,on Monday night told ITV News that Davies had written to her family saying she was "looking after the mothers of the world". An inquest into her death heard that her fellow residents had delayed telling her family that she had fallen out of the window for seven months and that Davies had spent seven months in hospital after the Christmas Eve fall, eventually dying on 3 August 1998.

The three women freed last month freed, who left the address before the arrests following a period of secretive discussions with police and a charity combating domestic slavery, have been identified as a 69-year-old Malaysian national, a 57-year-old Irishwoman and a 30-year-old Briton, called Rosie, who is believed to be the daughter of the Irishwoman and Balakrishnan.

As the background of the suspects emerged, Lambeth council came under pressure to explain why it did not appear to have acted on concerns about the 30-year-old woman, who is believed to have been held by the couple since birth.

The authority reportedly received a complaint from a member of the public in 1998 when the teenage captive, then aged 15, did not appear to be attending school. Detectives have found no official documentation for the woman other than a birth certificate.The flat where the five people lived in Peckford Place is a council property. But the council said it could not explain why it had housed the group there, or why it had not noticed that the 30-year-old woman had not been to school. A spokeswoman said the council could not go into detail about its contact with the Balakrishnan couple because officials were working with the ongoing police investigation.

"This is an extremely complex case involving a number of individuals going back decades. It is too early at this stage to provide the detail of any contact we may have had with them," she said.

The charity that was central to the release of the women, the Freedom Charity, has appealed to the media to respect the women's privacy as more detail about their life with the couple became public. "The women are under added pressure as the appetite increases to find out who they are," said Aneeta Prem, the charity's founder.

The Balakrishnan group's beliefs were mocked in the diary column of the Times, prompting speculation that it may have been a partial model for the Tooting Popular Front, the ludicrous political movement in Citizen Smith, the BBC sitcom, which began in 1977.

The Rev Bob Nind, who was the vicar of St Matthew's church in Brixton at the time, said he knew of the group by reputation as the most far-left among the many Marxist-linked groups at the time: "I remember very well that at the 1978 byelection after Marcus Lipton died, there were 10 candidates, and five were to the left of Labour. But even among these, the people from Acre Lane were known as being particularly doctrinaire, and quite centralist."

According to another history of far-left groups in the period, the Balakrishnans' Acre Lane community was broken up in a police raid in 1978, in which the couple were among 14 people arrested.