appears he was not abducted but simply walked off. and according to fellow soldiers, at least a half dozen of their comrades were killed trying to find him. the pentagon is not officially linked those deaths to the missing soldier, nor has he been charged with any crime. however -- >> the army will conduct a comprehensive review of all the circumstances regarding sergeant bergdahl's disappearance. and i think i would leave it there. >> reporter: and there are serious questions about whether bergdahl was trying to connect with the taliban. if that's true, if he willingly joined the enemy, that would likely nullify any responsibility of his fellow soldiers to bring him home. but even that gets tricky in a war like afghanistan, where alliances are murky, battle lines are vague, and a soldier can disappear in a cloud of questions. tom foreman, cnn, washington. "outfront" tonight matthew