Post mortems performed on the bodies of the British couple found murdered at their home in Mount Pleasant, Portland, last month revealed that they were shot before being burned.
Alford Anderson, 74, and his 71 year-old wife, Florence, were found dead on June 22, just days after filing a report with the police that more than $8 million had been stolen from their bank account.
Their burnt bodies were found at their home, which was also set ablaze.
The post mortems, which were conducted on Friday, revealed that Mr. Anderson sustained bullet wounds to the hand and other parts of the body, while his wife was shot in the upper body.
The Police High Command has assigned a special team from the Major Investigation Division to handle the probe.
The team was in Portland on Tuesday collecting statements and evidence.
Meanwhile, the prime suspect held in connection with the murder of the British couple was remanded on Tuesday when he appeared in court on fraud charges.
Saquino Farr, 24, who is a resident of Mount Pleasant, was charged last week with seven counts of obtaining goods by means of false pretence and conspiracy to defraud.
He appeared before the Portland Parish Court Tuesday morning, where his attorney presented arguments that Mr. Farr was given permission by the couple to carry out transactions.
Investigators alleged that over an unspecified period, Mr. Farr gained access to the debit card of the British couple and stole more than $8 million.
The cops say he used the money to purchase furniture, appliances and other items.
Mr. Farr was remanded until July 31 when his attorney is to apply for bail.