It took a while for Todd Beth to connect the dots and realize someone had hacked the pumps at his family's Healdsburg gas station.
One customer came in wondering about charges made on her account after she bought gas, but even she figured the problem lay elsewhere. But after several regulars made passing remarks about fraudulent charges suddenly appearing on their cards, Beth grew alarmed.
He called out a technician who opened the pumps and found the stories were no coincidence. Someone had installed electronic "skimmers" on two of the station's most remote pumps, stealing credit card information for an untold number of customers at Jerry's Valero on Dry Creek Road.
"It's a shock," Beth said. "You don't make a good name for yourself by having things like this happen to your customers. Obviously it's a real bummer."
The incident in April marked at least the second time in the past year that criminals have targeted Sonoma County gas stations with electronic devices that surreptitiously record customer debit or credit card information.
In November, the owner of Wiseman's Valero in Santa Rosa called police after finding two skimmers. In that case, the devices' poor installation shut down one of the pumps, prompting their discovery before any harm could be done.
But in Healdsburg, the criminals were more adept, installing skimmers that may have lay hidden for weeks, all the while gathering customers' data that beamed out through a wireless signal until they were removed on April 26.
One of the victims, a Healdsburg vineyard owner who declined to be identified, said she discovered the theft only this week when she opened her monthly statement. More than $3,000 in charges had been made at gas stations across Southern California. Her bank erased the charges, though she was amazed they hadn't noticed the fraud before she did.
"What I just couldn't believe was their security algorithm didn't pick it up," she said. "There was a charge of about $100 every single day at a gas station."
Beth said about 20 people have contacted the station about the problem with many more likely to have settled the matter with their banks. Most have been understanding, he said.
His dad, Jerry, who has owned the station since 1968, was among the victims. He learned his card had been compromised after he tried to use it at a restaurant at the same time someone in Southern California was running a counterfeited version.
Beth said he'd heard warnings about skimming but never worried much about it in small town in Sonoma County. Like many stations, the station's pumps were protected by a common key designed more to give access to technicians than to maximize security.
They've now invested in locks only they have keys to - the same step taken at Wiseman's Valero.
Authorities say skimmers have been a growing problem that has spread from Southern California into the Bay Area and now into Sonoma County.
In December, a gas station in Mountain View discovered a skimmer on its pumps, notifying authorities who rigged an alarm to notify them when the pump was reopened.
In the ensuing bust, Boris Tumasyan, 24, and Sarkis Sarkisyan, 23, both from Glendale, were arrested after officers said they found pump keys and gas station addresses in the men's van. The investigation led to six identical skimmers found at five locations in Mountain View and Los Altos. Together they contained more than 3,600 credit card numbers.
In January, two other Southern California men, David Karapetyan and Zhirayr Zamanyan, pleaded guilty in a cased involving the theft of more more than $90,000 from 200 people. The four-month skimming spree across Northern Californian ended in their arrest in Martinez.
During the investigation, officials found skimmers in Martinez, Benicia, Livermore, Hayward, Oakland, San Mateo and Sacramento.
"The problem is growing in our area over say the last year and a half," said Carl Chapman, Supervising Inspector with the Northern California Computer Crimes Task Force. "We have seen an increase in devices."
Skimmers can be all but invisible from the outside -- and in some cases take a trained eye to see even when the machine is opened. Chapman said card users get more protection by using credit cards than debit cards , which draw cash directly from accounts.
"If my credit card information is stolen, the credit card company is going be quicker to refund me," he said. "If someone gets a debit card card and withdraws money from a bank account, it's much harder to get that cash back."
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