Three people have been arrested in connection with an investigation into the deaths of a family of four in Northamptonshire.
Jifeng “Jeff” Ding, his wife Helen and their two daughters Alice, 12, and Xing, 18, were found stabbed to death at their home in Wootton, Northampton, in May last year.
Chinese businessman Anxiang Du, 52, who has not been seen since the day of the murders, is being sought by police.
He is a former business associate of Mr and Mrs Ding but their relationship had soured and was the subject of a court case which reached a climax in the week of the family’s deaths.
A man and two women have now been arrested on suspicion of conspiracy to assist an offender, Northamptonshire Police said.
Police said a woman in Coventry, a woman in Gloucestershire and a man in London were arrested.
All three have been interviewed and released on bail.
The arrests were made as part of a joint operation between the police forces and the East Midlands Special Operations Unit.
Three officers from the unit travelled to China – where family of the victims live – last month as part of the inquiry.
Detective Chief Inspector Tom Davies, who is leading the inquiry, said it was known that Mr Du also had contacts in China.
Anyone with information concerning the whereabouts of Mr Du is asked to contact police or Crimestoppers on 0800 555111, or via their website.