Clothes worn by Sophie Toscan du Plantier on night of murder sent to FBI for new analysis

The hope is that foreign police can provide a breakthrough to help solve the crime.

According to the Irish Independent's Senan Molony, who has been covering the case for almost three decades, the items - which include a blue dressing gown and Italian-made Fiorella boots - were brought to the US by gardaí to ensure continuity of evidence.

Given improvements in technology in recent years, the hope is that the elite resources of the Federal Bureau of Investigation could have the potential to uncover DNA from the killer.

Ms Toscan du Plantier bought a holiday home in the idyllic village of Toormore, West Cork in late 1993 – which she visited with her family on numerous occasions between 1993 and 1996.

The married mother-of-one's body was discovered on the laneway leading to the property at around 10am on the morning of Monday, 23 December 1996, triggering one of the biggest murder investigations Ireland has ever seen.

She had been bludgeoned with a stone and a heavy concrete block, and may also have been struck with a hatchet, which was later found missing from her house.

At the time of her brutal death, Ms Toscan du Plantier was wearing a white top and elasticated leggings, with a blue dressing gown.

The dressing gown, which has two sizeable tears, was forensically examined at the time.

The scientist who studied the garment concluded that there was "heavy blood-staining on the dressing gown, particularly at the collar area."

Their report continued: "I grouped blood on the dressing gown and found that it was consistent with Sophie Toscan du Plantier’s blood sample.

"No seminal staining was detected."

Despite the inconclusive initial findings, the dressing gown is viewed as a key piece of evidence that could contain some semblance of another person's DNA.

Several high-profile documentaries have been produced about the cold case, including 2021's Murder at the Cottage - created by Oscar-nominated director Jim Sheridan.

Last month, Sophie's father Georges Bouniol died at the age of 98.

He is survived by Marguerite Bouniol, his wife and Sophie’s mother.