CHESTERFIELD COUNTY, Va. -- The Social Security numbers of nearly 2,300 taxpayers were exposed and may have been compromised, because of a corrupt electronic file, according to Chesterfield County Commissioner of the Revenue Jenefer Hughes.

Earlier this month, the commissioner's office mailed out more than 8400 tax notices as part of an audit on personal property taxes. About a quarter of those notices had their Social Security numbers printed, along with their addresses, in the window of the envelope.

"I take full responsibility for it as the commissioner," said Hughes.

"It was just under 2,300 people were affected. As soon as we found the issue, we were about to identify each of those taxpayers and I prepared and sent a letter to each of them to let them know that their Social Security numbers had unintentionally been discovered," she added.

Hughes says about a dozen people have contacted her office, concerned about the breach.

The county is offering free identity theft monitoring and has put safeguards in place to prevent a recurrence.

Virginia law prohibits treasurers and commissioners from releasing taxpayers’ personal information and violators could face a civil penalty of $250 to $1,000 dollars

Hughes says the audit, which determined whether taxpayers mistakenly received personal property tax relief on cars registered for business use, will help the county collect more than $1 million in revenue.

"I don't want to minimize the issue, it's really a very serious issue, we took it very seriously here and I sincerely regret it," said Hughes.