About 1,500 customers of internet service provider Virgin Media have been warned that their PCs are infected with a malicious virus.
The targeted customers had fallen victim to the SpyEye trojan that steals log-ins for online bank accounts.
Letters have been sent to those affected, giving them advice on how to clean up their computers.
Virgin is understood to be the first UK ISP to give specific warnings to customers about viruses on their PCs.
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