Arsonists targeted a farmhouse at the childhood home and final resting place of Diana, Princess of Wales in the early hours of Wednesday.
The late royal’s younger brother Earl Spencer took to social media on Wednesday to reveal that the structure at Althorp House, Northamptonshire had been burned by vandals at around 1.30am.
He posted on X, formerly knwon as Twitter: "Stunned to learn that one of @AlthorpHouse’s farmhouses — fortunately, unoccupied at the time — was apparently burnt down by vandals last night.
"With thanks to @northantsfire for doing their very best. So very sad that anyone would think this a fun thing to do."
More details about the destruction of the farmhouse on the Dallington Grange were provided by the estate's gamekeeper Adey Greeno.
He said: “The farmhouse that we lost to a deliberate act of vandalism last night has now had to be razed to the ground for safety reasons. So sad. The world we live in.”
Northamptonshire Police said the incident had "not been recorded as a crime at present, but this could change if there is evidence to indicate it was started deliberately”.
Meanwhile, Northamptonshire Fire and Rescue Service said the two-storey building was "fully” alight when crews arrived.
The brigade told the BBC firefighters with breathing apparatus used hose-reel jets to contain the blaze and prevent it from spreading further.
One firefighter will reportedly remain on the scene with a water bowser to continue dampening down any remaining hotspots.
David Fawkes, chief executive of the Althorp Estate, said: "The house and farm buildings have been unoccupied for several years and the site is scheduled for redevelopment as part of the Dallington Grange development.
"The farmhouse was built in the late 18th Century, and it has been completely destroyed by the fire, but the surrounding outbuildings are undamaged. Our priority is to secure the site and make sure it is safe.
"We are very grateful to Northampton Fire and Rescue Service and the estate team for dealing with the fire so effectively. We don't know how the fire started."
Diana — the mother of Prince William and Prince Harry — lived in the Grade I-listed stately home from the time her parents John Spencer and Frances Shand Kydd divorced in 1969 to her marriage to King Charles, then Prince of Wales, in 1981.
The princess tragically died aged 36, alongside her companion Dodi Fayed, 42, and driver Henri Paul, 41, following a car crash in Paris in 1997.
She was burried on a small island in an ornamental lake — known as The Oval — within the grounds of the 13,000-acre country estate, which has belonged to the Spencer family since the 16th century.
Opened in July 1998, the memorial is visited by approximately 150,000 people a year.
In his 1998 book Althorp: The Story of an English House, Earl Spencer revealed the family’s decision to bury his sibling on The Oval, saying: “We all agreed that, with its beauty and tranquility, this was the place for Diana to be.”
