CONCORD, N.H. (WPRI) — Police in New Hampshire and Massachusetts are investigating after card skimmers were found at two popular stores.

The devices, which are used to steal people’s banking or credit card information, were allegedly attached to express checkout machines at Walmart and Market Basket locations on Oct. 17.

This type of scheme is happening around New England. Police said card skimmers were also found at Market Baskets in Nashua, Haverhill and Reading. Another skimmer was found in Somerville too.

The front and back of a card skimmer from Concord, New Hampshire.
(Courtesy: Concord Police Department)

There are some ways to help make sure your payment information isn’t stolen.

Check the chip reader

Police say a chip reader that doesn’t work is a “tell-tale sign” of a card skimmer. If the reader appears jammed, a customer would have to swipe their card instead, which could allow them magnetic reader to take their information.

Hide your PIN

In case there are hidden cameras, always hide your PIN with your hand while you type it.

Compare the card reader

Skimmers may appear bigger than normal card readers. If possible, look at others nearby to see if they look the same as the one you’re using. Police say the colors and styles should all match, while the graphics should be aligned and unobscured.

Look for signs of tampering

Check card readers for any obvious signs of tampering, such as damaged panels or broken security seals.

Move the card reader

Police say card skimmers and fake keypads are meant to be removed. If the keypad feels loose, you may have found a card skimmer.

Two suspects who allegedly installed card skimmers in Concord, New Hampshire on Oct. 17.
(Courtesy: Concord Police Department)

Police have determined the card skimmers in Concord were installed by the same two suspects, who they’re now trying to identify.

Anyone with information on the scheme or who thinks their information may have been stolen should contact Concord Police or Detective Stephen Hemming at (603) 225-8600.