Businesses in Penarth are being urged to stay vigilant following a number of burglaries in the past month.
South Wales Police is continuing to investigate after around 20 businesses in the Vale of Glamorgan have either been broken into or been subjected to an attempted burglary.
Police are advising businesses to make it clear there is no cash stored on the premises overnight to deter thieves.
"Common themes" of the crimes include the fact they happen overnight and money is taken from the till, with doors or windows smashed to gain entry.
Most recently, there have been break-ins at the Penarth Lawn Tennis Club and a shop on Windsor Terrace.
Both small independent businesses and larger stores have been targeted.
Detectives are reviewing forensics, speaking to witnesses and looking at CCTV as part of their investigation.
Abi Biddle from South Wales Police said: “Being a victim of burglary, whether it’s your home, your business, or where you work is a traumatic experience and we are working hard to put a stop to this recent rise in commercial burglaries.
“We believe that one or two groups of people are responsible because of the similarities in the offences.
“We would ask businesses to review their security systems and also make it clear that there is no cash on the premises overnight”.
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