A man has been charged with the murder of a husband and wife who were found dead at home by their daughter on Easter Sunday.
Luke D'Wit, 33, was charged with two counts of murder after Stephen Baxter, 61, and Carol Baxter, 64, were found dead at a home in Victory Road, on Mersea Island, near Colchester, at about 1.30pm on April 9, Essex Police said.
Officers were called by the ambulance service to concerns for the welfare of two people and found the married couple had died.
Initially, their deaths were being treated as unexpected and not suspicious and officers were working to establish the circumstances around their deaths, the force said.
But as a result of an investigation and toxicology analysis, two men and a woman were arrested on Thursday. A woman and a man have been released on bail.
Man in 30s dies after being stabbed in park sparking police probeD'Wit, of Churchfields, West Mersea, Colchester, was charged with two counts of murder, one count of possession of a Class A drug, and one count of theft. He is due to appear at Chelmsford Magistrates' Court on Saturday.
Detective Inspector Lydia George, who is leading the investigation, said: "This is a significant development in our investigation as we piece together the circumstances around the deaths of Carol and Stephen.
"I would like to thank everyone who has come forward to speak to us throughout this complex investigation."
A post-mortem examination gave a provisional cause of death for Mrs Baxter, 64, as combined fentanyl and promethazine toxicity with terminal bronchopneumonia.
The provisional cause of death for Mr Baxter, 61, was delivered as cardiomegaly and alcoholic liver disease with fentanyl intoxication.
Fentanyl is a powerful synthetic opioid that is similar to morphine but up to 100 times more potent. It is a prescription drug that is also made and used illegally - often as a substitute for heroin.
The couple founded Cazsplash, which sells corner and curved shower mats, in 2012.
Mrs Baxter had run the business since its inception, having also worked in adult education, while Mr Baxter worked for a real estate firm.
The duo were also both keen members of West Mersea Yacht Club, in Coast Road, which flew its flag at half mast following their deaths as a mark of respect.
Mersea resident John Akker said it was a "shock to locals", adding: "It is very sad news."
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