Cpl. Wassef Ali Hassoun, 24, will remain at Quantico until a team of repatriation experts determines he is ready to rejoin his unit, which could take weeks or months, Marine spokesman Lt. Col. Dave Lapan said.
Hassoun disappeared from a Marine base in Iraq June 20. He was initially listed as a deserter, but was changed to "captured" when video appeared of him apparently being held by kidnappers.
After the news media widely reported he had been beheaded, he showed up in Lebanon and ultimately alerted the U.S. Embassy in Beirut of his location. He was then turned over to military custody and taken to Germany for medical and psychological evaluation.
Hassoun reportedly promised his alleged kidnappers he would not return to service in the U.S. military.
His mysterious adventure is under investigation by the Naval Criminal Investigative Service.