Officers have made a further arrest in connection with the investigation into the deaths of four members of the Ding family in Wootton, Northamptonshire, in April last year.
A 22-year-old woman from Southend, Essex, was arrested this afternoon in Plumstead, London, on suspicion of conspiracy to assist an offender.
She will be interviewed at a local police station to where she was arrested.
Three people who were arrested yesterday (Wednesday 18 April) also on suspicion of conspiracy to assist an offender have been released on police bail.
The 54-year-old woman who was arrested in the Radford area of Coventry, the 39-year-old woman who was arrested in the Gloucester town centre area of Gloucestershire and the 25-year-old man who was arrested in the Islington area of London, were interviewed at local police stations yesterday and later released on bail.