Slavery suspects were arrested in the 1970s

The suspects bailed after three women were alleged to have been held as slaves for 30 years were previously arrested in the 1970s.

Police would not say why the man and woman, both 67, were arrested, or if they were convicted at the time — adding that the current investigation “will take considerable time”.

Scotland Yard said the pair were arrested on suspicion of immigration offences as well as in connection with the investigation into slavery and domestic servitude.