A group claiming to represent ISIS has hacked into Twitter and YouTube accounts belonging to the Pentagon. The "Cyber Caliphate", a hacker collective that claims to be linked with the terror group ISIS, infiltrated the Twitter account @CENTCOM (US Central Command) and posted a message that read: "AMERICAN SOLDIERS, WE ARE COMING, WATCH YOUR BACK. ISIS."

The hackers also posted a message to Pastebin that read:

"In the name of Allah, the Most Gracious, the Most Merciful, the CyberCaliphate under the auspices of ISIS continues its CyberJihad. While the US and its satellites kill our brothers in Syria, Iraq and Afghanistan we broke into your networks and personal devices and know everything about you. You'll see no mercy infidels. ISIS is already here, we are in your PCs, in each military base. With Allah's permission we are in CENTCOM now. We won't stop! We know everything about you, your wives and children. U.S. soldiers! We're watching you".

Twitter has acted quickly and suspended the account, but the hackers have posted zip files to Pastebin of what they claim is sensitive US Army information.

The group also appears to have gained control of the US Military Command's YouTube channel and uploaded pro-ISIS videos, including one called "Flames Of War". CENTCOM and The White House are yet to comment on the cyber attacks.