(ABC News) U.S. Army veteran has been arrested for allegedly fighting alongside an al Qaeda group in Syria and then bragging about it online.

Phoenix man Eric Harroun, who served in the Army from 2000 to 2003, was arrested Wednesday upon returning to the U.S. from Turkey, where he had described to FBI agents his bizarre journey to the front lines of Syria’s civil war with fighters from the al-Nusra Front, a designated terrorist organization also referred to as al Qaeda in Iraq.

According to charging documents, Harroun traveled to Turkey in November 2012 and eventually found people there who agreed to help him slip into Syria to help the rebels in January 2013.

Once in Syria, he linked up with al Nusra and allegedly participated in several battles against pro-government forces. In later voluntary interviews with FBI agents in Turkey, Harroun claimed to have shot at least 10 people, but said he was unsure if he killed anyone.

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