The U.S. Army's website was defaced and later brought down Monday, with the Syrian Electronic Army (SEA) claiming responsibility.
The SEA, a group of computer hackers supporting the government of Syrian President Bashar al-Assad, claimed to have posted several messages on Army.mil Monday afternoon. One graphic, showing Syrian troops, included the text, "The defender of honor, Syrian Arab Army."
Another message read, "Your commanders admit they are training the people they sent you to die fighting." The SEA took credit for the defacements through its Twitter account. A civil war has been raging in Syria since early 2011.
As of 5 p.m. Eastern U.S. Time, both Army.mil and Stratcom.mil, the website of the U.S. Strategic Command, the U.S. military operation in charge of nuclear missiles and military satellites, were down. Most other military websites seemed to be working.
One tweet from SEA seemed to suggest the hackers gained access through the Limelight content delivery network.
One cybersecurity vendor called the defacement "embarrassing." However, annoying vandalism isn't the biggest problem for U.S. government websites, said iboss Cybersecurity CEO Paul Martini. Instead, the Army needs to protect its sensitive data against the type of breach reported at the U.S. Office of Personnel Management last week, he said via email.
An Army representative wasn't immediately available to comment on the attack.
Grant Gross covers technology and telecom policy in the U.S. government for The IDG News Service. Follow Grant on Twitter at GrantGross. Grant's email address is firstname.lastname@example.org.