A Nottingham jeweller is offering a £10,000 reward for information leading to the arrest of the thief who broke into his city centre shop.
John Rose Jewellers, in Maypole Yard, off Clumber Street, was broken into during the early hours of Tuesday.
The offender apparently used a hammer and chisel to break down a rear wall before taking about 300 items.
Managing director of the store, Nick Myers, described many of the items as "irreplaceable".
He said: "It is annoying, frightening and very worrisome that people can come into the heart of the city and start demolishing walls to gain entrance to a premises."
He added: "Many of the items taken were vintage and second-hand and therefore irreplaceable.
"Some had been reserved for Christmas gifts and we are going to have to tell customers their chosen gifts have gone."
Paula Copse, who works at the store, said the staff were "distraught".
"It is very upsetting for everyone and the owners but it is important to show we are open and carrying on."
Police have appealed for anyone who saw anything suspicious in the area between 0500 and 0600 GMT to come forward.