A skimming device was found on a fuel pump in Bury St Edmunds last week.
It was found at Tesco’s filling station on St Saviours Interchange.
Police believe it was fitted between 5am on Thursday and 10.55am on Friday.
It was found above the box where the key pad and card slot are located on the pump.
Anyone who may have witnessed any suspicious activity around the fuel pumps, especially overnight, or who has any information, is asked to contact Pc Lisa Yorke at Bury Police Station on 101 - quoting reference BU/14/1123 - or Crimestoppers, anonymously, on 0800 555111.