Thieves have used sleight of hand to con shop staff in Broughty Ferry and Barnhill out of cash.
Police warned retailers to be on their guard against the scam, known as ringing the changes, after the Co-Op on Claypotts Road and Tesco Express on Dalhousie Road were targeted.
Two men in their thirties and of Asian appearance entered the Co-Op shortly after 6.30pm on Wednesday.
Notes were exchanged and, after the men left, it was discovered they had taken an additional two-figure sum.
The first man was 5ft 6in, stocky and wore a black leather jacket, white shirt and dark trousers.
The other was about 5ft 10in, slim and wore a blue jacket with grey sleeves.
