(CNN) -- A computer failure halted the processing of food stamp purchases in parts of the country Saturday, a Xerox spokeswoman confirmed.
A system shutdown began at 11 a.m. ET Saturday, spokeswoman Karen Arena said. She said Xerox -- which is a contractor for the program -- was working on the problem and planned a further statement later Saturday.
The food stamp program, officially known as the Supplemental Nutrition Assistance Program, or SNAP, allows many beneficiaries to present a payment card at grocery stores. Some of those transactions were being prevented Saturday in unspecified parts of the country.
The program is administered by the Department of Agriculture. The department's public affairs staff has been furloughed and its website was not being updated Saturday because of the partial government shutdown. A phone call to the office of the department's communication director was not answered Saturday afternoon.
Officials in several states said the computer problem was unrelated to the government shutdown.
An Ohio official said cash payments through SNAP cards were back online Saturday afternoon, but electronic purchases still weren't working, CNN affiliate WBNS-TV reported.
Benjamin Johnson, deputy director for the Ohio Department of Job and Family Services, told WBNS that SNAP users could spend up to $50 at stores by calling the phone number on the back of their card.
CNN affiliate KJRH-TV in Tulsa, Oklahoma, quoted Xerox spokeswoman Jennifer A. Wasmer as saying the shutdown happened during a test of the company's backup systems.
\"While the system is now up and running, beneficiaries in the 17 affected states continue to experience connectivity issues to access their benefits,\" Wasmer told KJRH. She said the glitch also affected payments through the Women Infants and Children, or WIC, program.
The list of affected states was not immediately available.