Nighthawk metal detectorists have struck again at one of Norfolk's historic sites, with their digging branded "heartbreaking" by the trust which protects the monument.
Damage at St Benet's Abbey, near Ludham, was discovered by charity bosses on Tuesday, November 8 and has been reported to the police.
Detectorists had dug into the ground at the scheduled monument, which is in the care of Norfolk Archaeological Trust.
Metal detectorists need permission from landlords to go metal-detecting and where a site is historically protected - as is the case at St Benet's Abbey - that permission would need to be given by the secretary of state, so it is illegal to dig there.
Natalie Butler, director of the trust, which is responsible for 10 archaeological sites, said it was the latest occasion when one of its sites had been targeted.
She said: "It is heartbreaking. You can never be sure what has been taken, what has been lost. It could have been absolutely anything.
"As soon as it's taken from the site so much is lost. It's not just the value of the object, but the context and the story of why it was at the site.
"We do our best to protect these sites and it is just so frustrating. The holes we found on Tuesday were really fresh, so it must have happened the night before or at the weekend."
The matter has been reported to Norfolk police, which the trust works closely with to prevent such crimes.
Norfolk police has previously used drones at St Benet's Abbey, as well as at the trust's site of Caistor Roman Town, to protect against gangs of metal detecting ‘nighthawkers’.
While many metal detectorists are responsible - and work closely with the museum service over finds, with Norfolk the county where most finds classed as treasure were found last year - there are groups which work illegally and without permission, often under cover of darkness.
Amid a rise in heritage crime at its sites, the Norfolk Archaeological Trust recently announced its staff at Caistor Roman Town would wear body cameras to help catch wrongdoers.
People who spot people using metal detectors illegally are urged to call police on 999 if the crime is still in progress.
People can also report anonymously to Crimestoppers on 0800 555 111.
HISTORY OF ST BENET'S ABBEY
The Abbey of St Benet at Holme lies close to the meeting place of the rivers Bure and Ant.
It was the only Norfolk monastery founded in the Anglo-Saxon period which continued in use throughout the Middle Ages, and the only monastery in England not closed by Henry VIII.
While much of the abbey's history is unclear, it is thought it occupied an isolated sand and gravel island from 1020 to 1545, becoming a popular pilgrimage site.
However, after William Repps - the then Abbot of St Benet's - was made Bishop of Norwich in 1530 and given St Benet's in the deal with the King, he began pulling down church buildings and selling stone in an attempt to clear his debt.
Later, a windmill was built inside the abbey gatehouse.
Today, the remains attract more than 30,000 visitors a year.
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