The ritual of swiping a card and pumping gas is familiar to anyone who drives a car. And over the past few months, thieves have been taking advantage of this, stealing personal financial information by installing devices that collect debit card information on or in gas pumps throughout the Greater Boston area.

“They are stealing people’s identity,’’ said John Chapman, the state’s undersecretary for Consumer Affairs and Business Regulation. “There is a huge black market out there for stolen credit card numbers.’’

Since January, these so-called skimmers have been found at gas stations in Bedford, Braintree, Bridgewater, Hingham, Westwood, and Quincy. The devices have ­become quite sophisticated and are not always easy to spot, Chapman said. Evidence ­suggests the information thieves are working in groups and have come to Massachusetts from out of state, he said.

To get the problem under control, the state has undertaken an awareness campaign. Earlier this month, it trained nearly a hundred local weights and measures officials to spot the signs of skimmers and put out a call for stepped-up inspections of pumps throughout the state. Fuel pump maintenance and repair companies have also been asked to look out for indications a pump has been tampered with. The 2,600 gas retail locations in the state also are getting alerted to the problem with their annual ­license renewal paperwork, Chapman said.

“We care about people’s private information,’’ he said, “and we want to protect them. A lot of that is done through awareness and education.’’

So what can you do to protect yourself?

The most foolproof solution is to pay inside and use cash. But if the convenience of the pay-at-pump option is too tempting, use a credit card ­instead of a debit card, a move that will shield your PIN, prevent thieves from getting direct access to your bank account, and limit your liability to $50 if your information is lifted. Try to stick to pumps closest to the main building or station attendant; thieves are less likely to have infiltrated pumps under closer observation.

If you notice a broken security seal on a pump, avoid using it and inform both station ­management and local law ­enforcement. And, as always, keep a close eye on your bank accounts and credit card statements so you can immediately spot any suspicious charges or withdrawals.

Have a consumer question or complaint? Reach Sarah Shemkus at seshemkus@gmail.com.