Council heritage chiefs have asked the University of Sussex to explain how artefacts from a listed building it sold in the summer appeared at auction.
Lewes District Council launched an investigation after a pair of large copper swans from Grade I listed Swanborough Manor were spotted in the sale.
Conservation officer Mike Lea has written to bosses asking for information about the swans and other items apparently removed from the manor grounds.
The swans, and an ornamental planter decorated with lion heads, were withdrawn from sale after the council asked why they were to be auctioned.
Mr Lea said: "We have not formed an official view because we have not got the factual information from the university.
"I have just simply asked it for that information, for each item in turn."
The new owners of Swanborough Manor, at Kingston, near Lewes, bought back a pair of urns, which had been in the grounds, at an earlier auction.
The manor, believed to date from the 13th Century, was listed in 1952.
It is a criminal offence to change the character of a listed building without permission.
Paul Millmore, director of the Society of Sussex Downsmen, alerted the council to the sale, where the pair of swans were expected to raise £2,000 to £3,000.
He said: "As far as the Downsmen are concerned, what is required is constant vigilance over the potential damage that can be caused to listed buildings when they change hands.
"If you own a listed building you have a duty to know what the law is, especially somebody like the university."
The university, which sold the manor in July, said a number of artefacts had been put forward for auction.
A spokeswoman said the Reading family, which bequeathed the building to the university in the Sixties, had been offered a pick of items since it was sold.
She said: "We have had a letter from Lewes District Council and we are investigating it."
Monday November 03, 2003
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