NSA denies site was hacked as Anonymous members claim credit

The National Security Agency (NSA) has said that a multi-hour outage of its website, NSA.gov, was caused by an error during scheduled maintenance rather than a hacking attack as rumoured on the Internet.

The NSA site was reportedly down for around eight hours, with some Twitter accounts associated with the Anonymous hacktivist collective taking credit for a malicious takedown of the site via a distributed denial of service (DDoS) attack, Gizmodo reported.

NSA officials, however, have stated that the site outage was not caused by outside actors, but rather was the result of "an internal error."

"NSA.gov was not accessible for several hours tonight because of an internal error that occurred during a scheduled update. The issue will be resolved this evening," an agency spokesperson said.

"Claims that the outage was caused by a distributed denial of service attack are not true," the spokesperson added.

The NSA has come under fire in recent months as former NSA employee Edward Snowden's leaked accounts of the agency's widespread surveillance operations have been reported by mainstream media outlets.

Recently, Germany's Der Spiegel reported that German intelligence, working with information from Snowden supplied via the news weekly, had concluded that the NSA had likely eavesdropped on German chancellor Angela Merkel's mobile phone communications.

President Barack Obama denied that any such activity had occurred in a phone call with Merkel. But the German chancellor was reportedly furious about the report and the episode has added more fuel to the fire for critics of the NSA's activities.