Shop windows were smashed and thousands of pounds of items were stolen in two town centre break-ins.
Spectacular Opticians and King and Partners estate agents in Downham Market were broken into on Sunday, September 8.
The incident is thought to have taken place at 5am.
Stuart Gibbs, managing director of Spectacular, said: "It happened at 5am on Sunday morning.
"Fifteeen pairs of sunglasses were stolen which was around £2,250 in costs.
"We have CCTV footage of somebody wearing a hoody and no features were visible at all. The person was relatively slight in build and knew exactly what they were doing. They made a beeline to the sunglasses so they have obviously been in the shop and checked it out.
"It was a mess, there was glass all inside the shop, it's been bordered up and the glass will be replaced today.
"It was broken into about five to six years ago with similar entry, so it may be the same person or gang that have done it again.
"Additional security measures will be put in place, it is already alarmed and we have CCTV but we're going to increase CCTV and make the doors more secure, replacing the plastic with metal reinforcement."
PC Lee Anderton, community engagement officer for Downham Market, said: "It's under investigation and officers are looking into it.
"Glasses were taken from the opticians and the estate agent was also broken into."
Asked if shop owners should be worried. Mr Anderton said: "No, not at all, as usual be vigilant and if you see anything out and about in the early hours, call the team and we can always check around. We'd rather be safe than sorry."
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