The reliance on external sources to complete credit-card process and other IT-related functions by brick and mortar companies is a prime factor behind customer data thefts over the past few years, Internet security giant Verizon has said.

"A chain with thousands of restaurants might have only 100 employees in information technology, so it uses outside vendors for many IT functions," says Bryan Sartin, director of the investigative response team at Verizon Business, and points out that this means a veritable lack of accountability on the third party's behalf.

Verizon, which investigates several highly publicized data thefts every year, says that of late restaurants and retail stores have accounted for more than fifty per cent of the data theft cases probed by the company, a company statement said. What's more insiders at the service providers are usually found to be the culprits of such data heists.

"Organized data-stealing gangs "go to the call centers, the Web development companies, the content development companies, the business partners, the people who pick up the backup tapes," the official says citing the case of a large Canadian oil company that complained of customers finding spurious charges on their credit cards.

However, Verizon also confirmed that several of the breaches were not a result of outsourcing but of functioning through unsecured wireless networks on the sub-contractors' systems. The only way around this mess is to ensure that access to data be limited to service providers.