Four concrete balls have been stolen from outside Blenheim Palace in Woodstock.

Estate managers at the world heritage site said the Duke of Marlborough was “distressed” by the theft, which took place on Friday night. The four balls, a foot in diameter, were removed from the crossroads in front of the stately home.

John Hoy, a spokesman for Blenheim Palace, said: “You can just about lift these concrete balls but you couldn’t get far with them, so they have either been rolled down the slope towards the lake, or put into a vehicle.

“We work very hard to preserve this world heritage site and it is immensely distressing that Blenheim Palace is being treated in this way.

“There have been one or two other incidents of vandalism — some Christmas tree lights were pulled down and a small gate was damaged in the park.

“This is not necessarily Blenheim being targeted and may have happened as a result of Christmas high jinks.

“The concrete balls are not particularly antique, but they are part of the fabric of the palace grounds and are probably worth several hundreds pounds each.

“The Duke is distressed by what has happened and we are working closely with the police over this isolated incident.”