UPPER MARLBORO, Md. – Officials in Prince George’s County Public Schools are scrambling to understand how a school employee inadvertently emailed personal information on 10,400 school employees to the district’s human resources personnel.

A human resources report emailed to some school staff Nov. 14 contained the social security numbers, dates of birth and employee ID numbers of 10,400 district staff, including 9,500 teachers, Gazette.net reports.

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District officials attempted to freeze the receiving email accounts when they got word of the mistake, but soon realized that copies of the report were forwarded to others outside of the school district, Prince George’s spokesman Max Pugh told the news site.

“No other details are available at this point,” Pugh said.

Pugh would not discuss who was involved with the mistake, what kind of potential punishment they might face, or why the report was forwarded to others, citing personnel privacy.

He said the district is investigating how the security breech happened to create procedures to prevent it from happening again. Employees were notified of the data leak Nov. 21, and they’re not too happy about it.

“People are angry, and I understand their anger,” teachers union president Kenneth Haines told the Gazette. “But anger isn’t going to get us anywhere.”

Pugh said the district is offering employees a free one-year membership with ProtectMyID credit monitoring service and he’s encouraging them to use it.

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“We’re being proactive in providing credit protection for anyone who may have been affected by the incident,” he said.

Northwestern High School Teacher Darla Heinz told the Washington Post she’s worried someone might hold on to her information for years before they take action.

“It’s all very troubling,” she said.

Others criticized the delay in notifying employees about the problem.

“They also said it is unclear to them how many people received their personal information or what might happen to it,” the Post reports.

In an email notification to employees the district said the original email containing the personal information was sent to a “select group of principals.” A different district spokesperson, Lynn McCawley, told the Post the email was forwarded to the personal email addresses of school staffers, who have since been contacted. School officials told the Post they’ve taken “appropriate action” against school employees involved in the data breech.

Many posters to the news story believed school officials owe taxpayers, and the school employees affected by the mishap, a better explanation of what happened, and the actions they intend to take against those responsible.

“How is it that they don’t have to explain in detail what action they are taking as ‘appropriate action’?” hamlet21 posted to the Washington Post site. “These people are public servants. Do they always forget about this mere fact? There needs to be a full accounting to the taxpayer.”