A nest belonging to England's rarest ant species has been stolen, a conservation charity believes.

Devon Wildlife Trust said the narrow-headed ants' nest was taken from its Chudleigh Knighton Heath reserve in Devon - the last stronghold for the species in England.

It claimed the surrounding ground showed "clear signs of digging with a spade" and it has reported the matter to Devon and Cornwall Police, which is urging anyone with information to come forward.