A second postmortem examination has failed to determine how a London businessman was murdered.
Police believe Mr Chohan's remains were buried here
The body of Amarjit Chohan, 46, was discovered near Bournemouth pier by a canoeist on 22 April.
His wife, Nancy, 25, their two young sons and Mrs Chohan's mother, all from Hounslow, west London, have not been seen since 16 February.
Police have named three men they want to trace in connection with the murder of the millionaire haulage operator and the disappearance of his family.
The first post-mortem examination of Mr Chohan's body failed to establish a cause of death.
Following a second examination on Tuesday, police said the "cause of death was unascertained but was consistent with asphyxiation".
A number of articles found during a five-day dig at a field near Stoodleigh, in Devon, where police say Mr Chohan's body was buried before being dumped in the sea, are being examined.
Police said they want to trace a former employee of Mr Chohan's, Ken Regan, 54, also known as Ken Avery, and a second man, 51-year-old William Horncy, also known as William Smith, from the Bournemouth area.
Mrs Chohan's brother has appealed for help in tracing the family
Mr Regan, who is from the Salisbury area, had known Mr Chohan for eight years, but only joined his company CIBA Freight as a HGV driver last year.
A third man, Peter Douglas Rees, 38, is described as "a close associate" of the two prime suspects.
Detective Chief Inspector Norman McKinlay, from the Metropolitan Police, said Mr Rees "had links to the Hampshire and Dorset areas" and asked anyone who had lent a boat to the suspects to come forward.
"At present we are unable to locate him. We do believe that he is still in this country and he's a close associate of Ken Regan and William Horncy."
Mr Regan and Mr Horncy are known to have boarded a ferry at Dover on Wednesday and officers are working with French police in the hunt for them.
Mrs Chohan, her sons Devinder and Ravinder, and her mother Charanjit Kaur, 51, have not been in contact with relatives or friends for two-and-a-half months.
Onker Verman, Mrs Chohan's brother, has appealed for help in tracing the family.
He said: "If anybody has got any information about my missing family, my mother and my sister and my nephews, they should come forward to trace my family and help the police with their investigation.
"I think my brother-in-law's business has something to do with their disappearance.
"That's all I can say at the moment. That's what the investigation is really - that the selling of the business had something to do with their disappearance."
Scotland Yard also said police had searched various addresses across southern England as part of their investigation.