Pentagon spokesman Lt. Col. Jeffrey Pool says it is yet to be found out whether the release of personal data belonging to US military personnel on social media is an outcome of a leak or a cyber attack carried out by the ISIS-linked hackers. It is yet to be found out whether the release of personal data belonging to US military personnel on social media is an outcome of a leak or a cyber attack carried out by the ISIS linked hackers, Pentagon spokesman Lt. Col. Jeffrey Pool told Sputnik on Wednesday. Recent US media reports revealed that the so-called ISIS Hacking Division used the Twitter account affiliated with infamous ISIS fighter Abu Hussain al-Britani to publish what they claimed to be names, emails, passwords, and phone numbers of individuals from the Air Force, the Marines, NASA and the Port Authority of New York and New Jersey. On Tuesday, the US Department of Defense stated it could not confirm the credibility of the information posted online. In January, the Twitter and YouTube accounts of the US military command were hacked by ISIS sympathizers calling themselves Cyber Caliphate. ISIS is a fundamentalist extremist group, primarily operating in Iraq and Syria, notorious for their multiple atrocities.