Their techniques vary but the basic idea is that the person inserts some sort of device in an A.T.M. or credit card reader in order to rapidly capture critical information. They later use this information to make purchases or create counterfeit cards.
The people involved in skimming often operate as part of international crime syndicates. The cybersecurity writer Brian Krebs has demonstrated that some have even found ways to hack A.T.M.s wirelessly, without touching the machines.
This investigation that led to Mr. Rosu’s arrest began in February, when U.S. Postal Inspection Service employees became suspicious of a package en route from Santa Ana, Calif., to a hotel in Palmer, Alaska, according to the complaint. Inside the parcel, inspectors found 555 gold magnetic cards bundled into groups. Alexander Laumb of the Seattle Division of the U.S. Postal Inspection Service began to try to piece together what was going on.
By March, Mr. Rosu, who was arrested in Australia in 2010 in a similar case, had become a focus of the investigation. Mr. Laumb learned that Mr. Rosu was caught trying to install a skimming device at a credit union in Groton Town, Conn. in October 2019 and that he had a history of skimming in other parts of the United States and the United Kingdom, according to the criminal complaint.
Mr. Rosu’s bank account showed that though he lived in Southern California, he made frequent “cashout” trips to Anchorage, according to charging documents. Ms. Vandergaw declined to offer specifics of how his system worked, but the complaint suggests that on these trips he would make dozens of small deposits using counterfeit cards he had encoded with data gleaned from his skimmer.
From August 2019 to March 2020, he deposited more than $180,000 this way, the complaint said. Back in California, he would withdraw the money, according to court papers.
Though inspectors had developed this theory, they had a problem: how to locate Mr. Rosu. And that’s where Enterprise Rent-A-Car came in. According to a police report, on a Saturday afternoon a week ago, a man was “becoming aggressive toward an Enterprise agent.”