U.S. mistakenly posts list of civilian nuke sites

"I should say I didn't regard the document as a security concern having reviewed it," he said. "I did find it interesting, but I didn't see anything there that constitutes a breach of security."

Breach went undetected by government

Gartner Inc. analyst John Pescatore, who advises several government agencies on cybersecurity issues, said one of the most troubling aspects about the incident is that the government didn't notice the breach till it was alerted to it by reporters. The incident speaks to a lack of process within the GPO for dealing with sensitive data at a time when the current administration is pushing government agencies to be more transparent, he said.

"The federal government is trying to push out more data, but they need to make sure they have the processes in place first," to prevent such accidents, Pescatore said.

In a statement sent via e-mail, a GPO spokesman provided no explanation for why a document marked as sensitive and not for publication by the president was publicly posted.

But the statement suggested that the accident may have stemmed from the sheer volume of such reports that the GPO processes. On average, the GPO produces "approximately 160 House documents each Congress," the statement said. During the 109th Congress, the GPO produced 157 reports, while in the 110th Congress, 161 reports were published, the statement said. The one listing nuclear sites "was received by GPO in the normal process and produced under routine operating procedures," the statement said.

"Upon being informed about potential sensitive nature of the attachment in this document, the Public Printer of the United States removed it from GPO's website pending further review," the statement said. "After consulting with the White House and Congress, it was determined that the document including the sensitive attachment [should] be removed from the website," it added.

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