Three people arrested in connection with the deaths of the Ding family in Northamptonshire last year have been released on bail.
Jifeng Ding, his wife Helen Chui and their children Alice and Xing were all stabbed to death on the day of the Royal Wedding.
Two women and a man who were arrested on suspicion of conspiracy to assist an offender have since been released.
Officers investigating the murder of the Ding family in Northampton have revealed they believe the prime suspect Anxiang Du is in Morocco.
A further arrest has been made in connection with the investigation into the deaths of four members of the Ding family.
Police face criticism over Ding murder