"Restarting the EBT system required time to ensure service was back at full functionality," spokeswoman Jennifer Wasmer said in an email. An emergency voucher process was available in some of the areas while the problems were occurring, she said.
U.S. Department of Agriculture spokeswoman Courtney Rowe underscored that the outage was not related to the government shutdown.
Earlier Saturday shoppers left carts of groceries behind at a packed Market Basket grocery store in Biddeford, Maine, because they couldn't get their benefits, said shopper Barbara Colman, of Saco, Maine. The manager put up a sign saying the EBT system was not in use. Colman, who receives the benefits, called an 800 telephone line for the program and it said the system was down due to maintenance, she said.
"That's a problem. There are a lot of families who are not going to be able to feed children because the system is being maintenanced," Colman said. She planned to reach out to local officials. "You don't want children going hungry tonight because of stupidity," she said.
Colman said the store manager promised her that he would honor the day's store flyer discounts next week.
Wasmer said the states affected by the temporary outage also included Alabama, California, Georgia, Iowa, Illinois, Louisiana, Massachusetts, Maryland, Mississippi, New Jersey, Oklahoma, Pennsylvania, Texas and Virginia.
Ohio's cash and food assistance card payment systems went down at 11 a.m., said Benjamin Johnson, a spokesman for the Ohio Department of Job and Family Services. Johnson said Xerox asked retailers to revert to a manual system, meaning customers could spend up to $50 until the system was restored.
Illinois residents began reporting problems with their cards - known as LINK in that state - on Saturday morning, said Januari Smith, spokeswoman for the Illinois Department of Human Services.
Smith said that typically when the cards aren't working retailers can call a backup phone number to find out how much money customers have available in their account. But that information also was unavailable because of the outage, so customers weren't able to use their cards.
"It really is a bad situation but they are working to get it fixed as soon as possible," Smith said.
In Clarksdale, Miss. - one of the poorest parts of one of the poorest states in the nation - cashier Eliza Shook said dozens of customers at Corner Grocery had to put back groceries when the cards failed Saturday because they couldn't afford to pay for the food. After several hours, she put a sign on the front door to tell people about the problem.
"It's been terrible," Shook said in a phone interview. "It's just been some angry folks. That's what a lot of folks depend on."
Mississippi Department of Human Services director Rickey Berry confirmed that Xerox, the state's EBT vendor, had computer problems.
"I know there are a lot of mad people," Berry said.
Sheree Powell, a spokeswoman for the Oklahoma Department of Human Services, started receiving calls around 11:30 a.m. about problems with the state's card systems. More than 600,000 Oklahomans receive SNAP benefits, and money is dispersed to the cards on the first, fifth and 10th days of every month, so the disruption came at what is typically a high-use time for the cards.
Oklahoma also runs a separate debit card system for other state benefits like unemployment payments. Those cards can be used at ATMs to withdraw cash. Powell said Xerox administers both the EBT and debit card systems, and they both were down initially.
Powell said that some grocery store cashiers had been speculating that the federal government's shutdown caused the problem, but state officials have been assured that that is not the case.
Powell said Oklahoma's Xerox representative told them that the problems stemmed from a power failure at a data center.
"It just takes a while to reboot these systems," she said.
Associated Press writers Lisa Rathke contributed from Montpelier, Vt., Dan Sewell from Cincinnati, Tom Murphy from Indianapolis, Sara Burnett from Chicago, Emily Wagster from Jackson, Miss., and Mary Clare Jalonick from Washington, D.C.