The craft store chain revealed last week that PIN pads in its Chicago-area stores had been tampered with, as crooks tried to steal customer card information.

In an update, it now says that it has identified 90 suspicious pads in 20 states around the country with exposed transactions occurring between 8 February and 6 May.

About 100 customer debit cards have been reported used in fraudulent transactions so far, says Michaels, which has removed 7200 pieces of hardware from its 964 stores as a precaution and will replace these over the next two weeks.