'Substantial reward' offered over £700,000 raid at Goodwood House
A "substantial" reward has been offered after Lord and Lady March were assaulted by a burglar who stole £700,000 of family heirlooms from their stately home.
The undisclosed sum is being offered by insurers amid a search to trace "irreplaceable" property stolen from Goodwood House near Chichester, West Sussex.
Lord March - the founder of the Goodwood Festival of Speed - and his wife were tied up and assaulted during the break-in at the 17th century property on January 13.
Detective Inspector Til Sanderson, from Surrey and Sussex major crime team, said Interpol had been alerted along with dealers, pawnbrokers and auction houses.
Mr Sanderson said: "Much of this treasured property is irreplaceable and my team, working closely with Lord and Lady March and the Goodwood Estate, is making every effort to trace it and identify those responsible."
He added: "I hope the offer of a substantial reward by the insurers, for information leading to the recovery of important items of jewellery and personal effects of historical significance, will encourage anyone who knows anything to come forward.
"We will continue to liaise with them as part of our investigation. My team are seeking forensic evidence in this case and intelligence from other forces regarding similar offences."
Lord March issued a statement following the raid, saying the couple were recovering and "entirely focused" on helping the police.
At around 4.30am, Lady March was disturbed by an intruder who broke in via an upstairs window using a ladder, before pushing her and striking her husband, causing an injury to his ear.
Lady March was then forced to open a safe before the man helped himself to jewellery. The couple were bound, then the robber escaped with his haul of valuable items.
Lord March, who founded the Goodwood Festival of Speed in 1993, and his wife were "devastated" at the theft of "priceless" items, police said.
Treasures, including an 1820 diamond tiara worth nearly £400,000, diamond necklaces and several luxury watches, including antique Rolex and Girard Perregaux timepieces, were stolen.
Other items taken included an emerald intaglio and diamond ring from 1800, engraved with the Duchess's coronet and monogram CL for Louise de Keroualle, mistress of Charles II.
More than 40 items were stolen including emerald, diamond and sapphire rings, earrings, bracelets and necklaces.
A 26-year-old man from Hampshire was arrested and released on bail until February while investigations continue.