A cash box was stolen Patisserie Valerie in Peterborough in early hours of the morning (Monday, February 12).
Thieves made off with the undisclosed amount of money in the early hours of the morning after smashing the door to get in.
Police were called at 1.30am this morning and are appealing for witnesses to come forward.
The eaterie in Cathedral Square, which sells handmade cakes and pastries and has breakfast and lunch menus, had a note on its door earlier saying it was closed, but it had reopened by lunchtime.
The Peterborough Telegraph has attempted to contact Patisserie Valerie for comment.
Anyone with information is asked to call Cambridgeshire police with the crime reference number: CF0081560218.