A triptych painting that was kept in an almshouse chapel has been valued at up to £3.5m by auctioneers.
St Johns' Almshouse, in Sherborne, Dorset, said it received the shock news after giving the altarpiece to Sotheby's auction house for safekeeping during renovation work.
Experts identified it as the only surviving work of an unknown painter who was active in Brussels in the late 15th Century.
The triptych will be auctioned on 3 December to raise money for new accommodation for Sherborne people.


