The two suspects behind the alleged domestic slavery of a 57-year-old Irish woman and two others are of Indian and Tanzanian origin and came to the UK in the 1960s.
British police said that two of the three victims met the male suspect in London "through a shared political ideology" and that they lived at an address which could be called a "collective".
Metropolitan Police Commander Steve Rodhouse explained that at some point the collective came to an end but that the women continued to live with the suspects.
"How this resulted in the women living in this way for over 30 years is what are seeking to establish, but we believe emotional and physical abuse has been a feature of all the victims' lives."
A 69-year-old Malaysian woman, a 57-year-old Irish woman and a 30-year-old Briton were rescued from a house in Lambeth, south London, last month, after one of the women called a support charity asking for help.
The suspects, a man and woman both aged 67, have been released on bail.
"Emotionally fragile and highly vulnerable"
Investigators believe the youngest of the alleged victims could have spent her entire life as a domestic slave.
Cmdr Rodhouse explained: "The 30-year-old woman does have a birth certificate; however that is all the official documentation we can find. We believe she has lived with the suspects and the other victims all her life, but of course at this early stage we are still seeking out evidence."
Scotland Yard revealed that part of the agreement when the women were removed from the address on October 25th was that police would not at that stage take any action.
The exact location of the property where the women had been living has not been revealed and police say they are "taking every step" to protect the "emotionally fragile and highly vulnerable" victims.
"Five times as many calls" to helpline
Aneeta Prem, founder of Freedom Charity, which received the call from the Irish woman that led to the discovery, said they had seen "an extraordinary rise in calls" to their helpline since the story broke.
"We received five times as many calls in 24 hours as we normally do in one week and are needing to increase our resources to cope with this extra demand.
"These women have had traumatic and distributing experiences, which they have revealed to us. What needs to happen now is that the three victims, who have begun a long process of recovery, are able to go through their rehabilitation undisturbed, without being identified."
