MANHATTAN (CN) - For 40 minutes on Monday, hackers posted ISIS propaganda and purported military documents on U.S. Central Command's Twitter and YouTube accounts, before both accounts were suspected.
The banner over both social media pages bore a picture of a headscarf-masked militant next to the words "CyberCaliphate" and "i love you isis."
President Barack Obama was giving a speech on cybersecurity at the time of the Monday morning breach.
The Twitter account hijacker posted supposed military documents, including address information of U.S. armed forces personnel and what appeared to be a map of North Korean nuclear facilities.
Various users quickly traced the postings to various documents that already existed on the public domain, and Pentagon spokeswoman Cmdr. Elissa Smith later confirmed that "no classified information was posted and that none of the information posted came from CENTCOM's server or social media sites."
While CENTCOM's Twitter account shut down roughly 40 minutes after the breach, its YouTube account remained active somewhat longer.
The Pentagon spokeswoman emphasized that both sites, which "reside on commercial, non-Defense Department servers," were temporarily taken offline as the breach is investigated.
"CENTCOM's operational military networks were not compromised and there was no operational impact to U.S. Central Command," Smith added. CENTCOM will restore service to its Twitter and YouTube accounts as quickly as possible. We are viewing this purely as a case of cybervandalism."
Former FBI agent Ali Soufan, who interrogated senior al-Qaida members before criticizing the CIA's torture program in his book "The Black Banners," took to his Twitter account to raise skepticism that the hackers were who they claimed to be.
"I doubt they are ISIS," Soufan tweeted. "ISIS never calls themselves ISIS."
Soufan added later that members of the group typically describe themselves as "Islamic State" or "Islamic Caliphate," rather than the more geographically restrictive acronym for Islamic State of Iraq and Syria.
While Smith said DoD and law-enforcement authorities are being notified "about the potential release of personally identifiable information," the FBI's national press office had no comment about the investigation.
Prior to the hack, the last Twitter post from CENTCOM was a retweet of announcement that France would "deploy aircraft carrier to fight ISIS."
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