Stately home raided by burglars who snatched priceless artefacts King Edward VII gave to his lover

A stately home was raided by a gang of sledgehammer-wielding burglars who snatched priceless artefacts King Edward VII had given to his lover, police have revealed.

The thieves ransacked Sudeley Castle in Winchcombe, near Cheltenham, "under cover of darkness" then sped off in a 4x4 in the early hours of September 8.

They forced their way into the exhibition area of the 15th Century building, smashed a display case then grabbed the jewellery and heirlooms.

Among the items taken was a Cartier watch monogrammed with AK, the initials of King Edward VII's mistress Alice Keppel, and a book of extracts by writer Sydney Smith that he gave to Kepple during their affair in the early 1900s.

Sudeley Castle's owner Lady Ashcombe told The Telegraph that she and her family were "incredibly shocked and devastated" by the burglary.

It happened just a week before a 25kg toilet made from 18-carat gold was stolen from Blenheim Palace in a similar raid 30 miles away.

The toilet's creator, conceptual artist Maurizio Cattelan hailed the thieves as "great performers" for the speed at which they managed to wrench it from the wall, where it was plumbed in.

Lady Ashcombe said the thieves at Sudeley were in and out of the property in as little as 16 minutes and had managed to dodge motion detector alarms.

She believes someone must have visited the exhibition then tipped off the burglars.

A £10,000 reward has been offered by Sudeley Castle's insurer for the return of all the items in an undamaged state.

Lady Ashcombe said in a statement: "We are all saddened to learn of this burglary. There were beautiful artefacts on display for everyone to enjoy and were very precious to me personally".

Alice Keppel was the most famous mistress of King Edward VII, the eldest son of Queen Victoria and Prince Albert, whose lovers are rumoured to have included Winston Churchill's mother Jennie Churchill.

Keppel and the future king met in 1898 when she was 29 years old and he was 56. Keppel was married to George Kepple, the son of an earl, while the future king was married to Alexandra of Denmark.

The youngest of nine children, Keppel was the great-grandmother of Camilla, Duchess of Cornwall, and the grandmother of Lady Ashcombe's late husband.

The stolen items, known as the Alice Keppel collection, were accumulated by Lord Ashcombe.

Sudeley Castle & Gardens, where Hollywood actress Elizabeth Hurley got married to Arun Nayar in 2007, said in a statement: "While the monetary value of the objects varies, their historical and cultural significance is priceless.

"They also hold irreplaceable sentimental value for everyone at the Castle and Lady Ashcombe is deeply saddened by the incident."

Detectives from Gloucestershire Constabulary are examining CCTV of the burglary, which shows four people approaching the property with a chair, sledgehammer and large bag.

Detective Superintendent Steve Bean said the items are "very distinctive" and have "a great deal of historical and financial value", so should be easy to identify if the thieves try to sell them on.

He added: "This burglary happened under cover of darkness, but it is still possible that someone may have witnessed suspicious behaviour at or near the property in the hours leading up to it or afterwards, and may be able to help us identify the offenders."

Anyone with information about the burglary is asked to call Gloucestershire Constabulary on 101 quoting incident 110 of 8 September.