The Syrian Electronic Army is taking credit for hacking the U.S. Army website.
The website was taken offline Monday afternoon after it started displaying the pop-up message, "Your commanders admit they are training the people they have sent you to die fighting." Army.mil was still down more than two hours later.
The pro-Bashar Assad Syrian Electronic Army tweeted a screenshot of the message, which it called "One of #SEA messages left on the US Army website."
The Pentagon did not immediately confirm which group was behind the intrusion.
The Syrian Electronic Army has previously taken credit for hacking media outlets including the International Business Times, the New York Times and the Guardian.
The cyberintrusion comes on the heels of a bombshell report that hackers suspected to be from China broke in and stole personal information belonging to as many as 4 million federal workers.
A spokesman for the U.S. Army did not immediately respond to a request for comment.
U.S. government websites have been a popular target for cyberattack as of late; Islamic State terror group sympathizers recently attacked the Twitter account for U.S. Central Command in January.
The Syrian Electronic Army broke into the Twitter account belonging to the Associated Press in April 2013, posting a false message that claimed there were explosions at the White House and that President Barack Obama had been injured.
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