PF Chang's swipes cards manually in US after breach

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P.F. Chang's China Bistro said it has begun manually swiping payment cards at all U.S. restaurants in the wake of a data breach to ensure that transactions are secure as investigators figure out how attackers accessed its systems.

The operator of Asian-themed restaurants disclosed the rare move to revert to manual equipment, providing customers with carbon copied receipts, after "a security compromise'' resulted in the theft of an unknown number payment card numbers from its restaurants. It has so far provided few details about the incident.

P.F. Chang's had said on Tuesday that it was investigating a possible breach, joining a growing list of major U.S. merchants involved in payment card breaches that begin late last year with Target Corp

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"We have moved to a manual credit card imprinting system,'' Chief Executive Rick Federico said in a statement emailed to Reuters early on Friday. "This ensures our guests can still use their credit and debit cards safely in our restaurants as our investigation continues.''

Madeline Aufseeser, a senior credit card processing analyst with Aite Group, said the move to use manual swiping machines known as "knuckle busters'' would prevent hackers from getting any more payment card numbers but had other tradeoffs.

"It makes a lot of work for the restaurant and they may end up eating a lot of tickets because they won't get immediate authorization on the spot,'' she said.

The Arizona-based company, which operates over 200 restaurants, has set up a website with information about the investigation being conducted by the Secret Service and private forensics experts:

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