Various Walmart locations in Central New York were the target of skimming devices at their registers over the last week or so, and more cases of credit card skimming are popping up across New York, police said.

The devices can be used to steal account information from customers. Police say shoppers may want to add an extra note to their shopping lists when paying with a card: "Check for a credit card skimming device." 

Officials say at least seven Central New York locations were targeted during the Fourth of July weekend. The devices are used to steal account information from unsuspecting customers. 

As of Tuesday morning, the Oswego County Sheriff's Office is looking into the latest incident at the Walmart in Central Square.

Other locations targeted recently include Auburn, Camillus, Cortlandville, East Syracuse, Fulton and Oswego.

New York State Police say shoppers are reminded to check for inconsistencies with the equipment when swiping their cards. Signs may include loose-fitting covers, misaligned card readers, or an oversized appearance.

New York State Police say the devices have been found at more than a handful of Walmart stores in New York state recently. It looks like a typical card reader.

“The front looks the same. It actually has the same notification and title on top of the actual device. And so you, to the naked eye, wouldn't notice. These are getting more and more professional, if you will, and they're realizing that they have to be as perfect as they can," said New York State Police Troop D Trooper Jack Keller.

Police said the devices record the information a user puts in, such as a card’s swipe and its pin number. On the inside is an antenna.

“It's a Bluetooth technology. And what that means is somebody who set this device up will come back either the next day or maybe hours later, knowing the device has captured your information. Instead of taking the device off, they will actually use an app, probably on their phone, and then walk up to that same register and they would press that app and that app would then take that and download all your information," said Keller.

Police are urging shoppers to keep an eye on their accounts. Sometimes, fraudulent purchases start out in smaller amounts, eventually leading to more expensive purchases.

“What we're seeing internationally in the crime groups is that they will use that information that you've stored into that device and create their own version of the credit card that you have or sell it online to these crime companies, these criminals abroad, that will use that information and then somehow hack into your account or purchase things on behalf of your account," Keller said.

Police said these skimmers are snapped onto the card reader, so people could check for a skimmer by tugging on the reader to check if there’s something that will come off.

If there’s a loose-fitting cover, a misaligned card reader, or an oversized appearance then it could be a skimmer. Police said some card readers will have stickers on them to show whether they’ve been tampered with.

Skimmers have been found at more than a handful of stores in Central New York, and another was just found at Painted Post in the Southern Tier.

State Police believe the same three people are involved in these cases, and are asking for the public’s help in identifying them.