大象传媒

Jifeng Ding, his wife Helen and their two daughters were stabbed to death in their home over the weekend.

Northants Police say they're looking for 52 year old Anxiang Du, a businessman of Chinese descent currently living in Coventry and working in Birmingham.

His family says he went to work as normal on Friday morning but he hasn't been seen since.

Police revealed that he wrote a suicide note shortly before the murders were thought to have been committed.

Detectives investigating this case believe the Ding family was targeted because of their business links with Mr Du.

Whilst police believe this wasn't a random attack on the Dings - officers are advising people not to approach Mr Du because of concerns about his mental state.