(WIRED) -- The U.S. Marine Corps has banned Twitter, Facebook, MySpace and other social media sites from its networks, effective immediately. The Marine Corps fears that social media sites such as Facebook could pose a security risk. "These internet sites in general are a proven haven for malicious actors and content and are particularly high risk due to information exposure, user generated content and targeting by adversaries," reads a Marine Corps order, issued Monday. "The very nature of SNS [social network sites] creates a larger attack and exploitation window, exposes unnecessary information to adversaries and provides an easy conduit for information leakage that puts OPSEC [operational security], COMSEC [communications security], [and] personnel... at an elevated risk of compromise."
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U.S. Marine Corps bans Twitter, Facebook, MySpace and other social media sites
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Order, issued Monday, states that information on the sites poses a security risk
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The Marines' ban is effective immediately and will last a year
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U.S. Army recently ordered all U.S. bases to provide access to Facebook
And they will continue to allow access to the military's internal "@placeholder-like services."