The Harford County Sheriff's Office is warning people who use ATMs to be aware of skimmers. Several theft cases have been reported in the last month.
Deputies say they usually get calls about skimming during the holiday season.
With every swipe, there's a possible swindle.
"They're targeting the times when people -- there's a lot of people out, a lot of people using their cards, a lot of people spending money," Deputy 1st Class Stavros Kalambihis said.
People are spending money and paying little attention.
"They go state to state, all up and down the East Coast, West Coast and throughout the entire United States of America," Kalambihis said.
This six year veteran says the thieves who use skimmers are waiting to get their next dollar.
"It's not the businesses who are really at fault. They have great surveillance cameras. They have great attendants who will really be on the up and up and keep an eye on things in their stores," he said, referring to the businesses that have been impacted by skimmers.
Most recently, investigators are looking for a man who's accused of stealing information from a victim's bank card in November.
The skimmers can range from low-budget to very sophisticated, that's why deputies say whenever you use an ATM, jiggle the machine to see if anything comes loose or make sure there are blockers in place.
"Sometimes it looks just like the scanner that's already on the machine itself. Sometimes it's literally a wire on the back of a machine," Kalambihis said.
ATM users say it's scary.
"It's disturbing certainly during this time of year especially," one customer said.
As shoppers head to stores this holiday season, deputies are warning them to watch their wallets and their bank statements.