He said 47 officers were now working on the case. Detectives are looking at files from the inquest of 44-year-old Sian Davies, who in 1997 fell from a window at a house occupied by the leftist group in Herne Hill.
A coroner described Davies' death as "mysterious". Davies was the mother of the youngest rescued woman, who is now 30. Her daughter's birth certificate shows that she was named Prem Maopinduzi Davies, but now calls herself Rosie.
Rosie told neighbours that she had been adopted by the group's leaders, Comrade Bala and his 67-year-old Tanzanian-origin wife, Chanda.
The couple were arrested and bailed last week on suspicion of domestic servitude, false imprisonment, assault and immigration offences.
Josephine Herivel, 57, another rescued woman, is the daughter of an Irish codebreaker of the second World War from Bletchley Park, who cut off contact with her family after joining the group.
Authorities in Kuala Lumpur have now confirmed that the oldest of the rescued women is Siti Aishah Abdul Wahab, 69, who came to London in the early 1970s to study while wanted by police in Malaysia for left-wing activities.
Her sister, Kamar Mautum, flew into Heathrow yesterday, hoping to meet up with her.
