Posing as official government bodies, PR firms are being asked to pay to comply with the act, yet companies need only register with the ICO where necessary.
The fake agencies have up until now targeted nurseries, airports and recruitment agencies.
'If a business gets a letter demanding money to register under the DPA, this will be a scam,' said ICO chief operating officer Simon Entwisle.
The letters use threatening language and are on official looking paper
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