A credit card skimming device was found at a gasoline station in Fontana , promoting the Fontana Police Department to issue a warning to residents about the dangers of this type of fraud . On July 28 , officers responded to a call from the Circle K gas station located in the 16900 block of Foothill Boulevard , where the manager noticed what appeared to be a credit card skimming device attached to the inside of gas pump number 12 . The pump was located as far from the cashier as possible . A suspect had used a master key to open the gas pump and install the skimmer device . This particular device did not appear to transmit information , which means the information was stored on the device for later retrieval by the suspect . There was no way to tell how long the device had been in place . The location is now adding extra security features to each pump in order to prevent future installation of the devices . " If you believe your card information has been compromised , you are encouraged to call your creditor or banking institutions to report right away , " said Martha Guzman - Hurtado , public information coordinator for the Police Department . Credit card skimmers are installed by thieves to clone the credit / debit card information of unsuspecting customers . This type of fraud is a growing concern at gas pumps and ATMs across the United States . The skimming devices read the magnetic strip from the cards ; often there is a hidden camera that picks up the keypad clicks for debit card PINS . The stolen information can be stored or transmitted to the crooks , who then use it for fraudulent purchases , or with debit cards to make counterfeit cards to withdraw cash from the victims ' account at ATMs . ;