Michaela, 27, daughter of Tyrone GAA manager Mickey Harte, was strangled on her honeymoon in January 2011.
Her body was found in the bathroom of her hotel suite in the four-star Legends resort by her husband John.
She had been choked to death and left in a bathtub. Police said she was murdered after disturbing thieves when she went to the couple’s room to get biscuits.
Arrests of suspects, followed by a new trial is likely after French forensic experts called in to assist the investigation uncovered fresh DNA evidence on an electronic keycard found in the room.
According to local media, the country’s Director of Public Prosecutions, Satyajit Boolell, said four new suspects have now been identified. He is said to have described the test results as “fresh and compelling evidence”.
A forensic expert from Bordeaux in France visited the Indian Ocean island at the beginning of last month, in the company of officers from the Mauritius Scene of Crime Office and those of the Forensic Science Laboratory.
In the region of 300 pieces of evidence were then sent for further scientific analysis to a forensic laboratory in Bordeaux. Interviews were also conducted with 600 current and former staff of the hotel which has since been renamed the Lux Grand Gaube.
Among the items re-examined by the French experts is the electronic keycard believed to have been used by the killer to gain entry to the bedroom. It was found by police on the day of the killing and is understood to be central to building a new murder case.
At the time, Superintendent Yoosoof Soopun, from the Mauritius police force, said there had been no break-in or sign of forced entry to the hotel room: “Whoever killed her definitely used an electronic card,” he said.
A source from Mauritius said that the new DNA analysis conducted in France was more sophisticated than tests conducted two years ago when two men charged in connection with the murder were acquitted by a jury after just two hours of deliberation.
Sandip Moneea and Avinash Treebhoowoon were cleared of the newlywed’s murder by a jury at the Supreme Court in the capital Port Louis in July 2012. According to the local source, police and the DPP are confident that they can build a compelling case against at least some of the new suspects.
All of them are former workers at the hotel which is in the centre of the fishing village of Grand Gaube, close to Grand Bay in the north-eastern corner of the island.
Stung by criticism of the original investigation, a new team of detectives was appointed after the 2012 trial. It was reported last year that they had identified a new suspect but no charges were brought.
The Harte and McAreavey families, who have previously been critical about what they claimed was a lack of progress in finding the killers, were told of developments in the case on Monday and are awaiting further details.
In June, the family said criminal investigations into her death seemed to have ground to a halt. In a statement in June, the McAreavey and Harte families said they remained determined to see justice done.
A spokeswoman for Michaela’s relatives said they were aware of the case’s progress. “They have been told of new developments in the case but we don’t know the exact extent of those developments and, therefore, cannot verify the veracity of reports from Mauritius,” the spokeswoman said.
The manager of the Lux Grand Gaube did not respond to a request for comment on the developments.