Peter Sommer cited in an article titled
"Hackers pilfer millions of credit card numbers"

"Five million credit card accounts were compromised when computer hackers broke into a company that processes US transactions on behalf of Visa and Mastercard." ....

"The revelation of the security breach, which took place some time last week, is worrying, say computer security experts."

Peter Sommer, at the London School of Economics’ Computer Security Research Centre, agrees. He says the majority of large-scale credit card thefts are carried out against poorly designed internet sites.