(CNN) The Twitter account for U.S. Central Command was suspended Monday after it was hacked by ISIS sympathizers -- but no classified information was obtained and no military networks were compromised, defense officials said.

A series of unusual tweets were published with apparent warnings from ISIS, as well as links, images and Pentagon documents that reveal contact information for members of the military.

The first tweet was published at about 12:30 p.m. ET and read: "AMERICAN SOLDIERS, WE ARE COMING, WATCH YOUR BACK. ISIS."

The account's profile photo became a black-and-white image of a person wearing a Keffiyeh, or scarf, around their head.

"CyberCaliphate" and "i love you isis" were sprawled out in white letters against a black screen at the top of the Twitter page.

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