The hackers may have accessed a server containing the names, Social Security numbers, birth dates and financial records of 12,000 Green Mountain State residents who are at least three months behind on child support payments.
However, the New England Credit Union supplied the state's server with the personal information of 58,000 people who did not owe child support, state officials said in press reports.
Cynthia LaWare, secretary of the state Agency of Human Services, told the Associated Press that the state has no evidence that the personal information has been used illegally.
The state will send letters to affected individuals this week, she said.
The Vermont State Police and the FBI have been notified of the breach, LaWare has said in published reports, adding that the affected server has been taken offline.
Earlier this month, hackers used a trojan to access the personal information of an unknown number of customers of TJX Companies stores, which include T.J. Maxx and Marshalls. A banking association reported this month that the personal info had been used in fraudluent purchases.
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