you exclusively -- are bur viewed an affair who abandoned his position. what does he tell you? >> reporter: that's right, we did. this also helps explain that why i.s.i.s. was able to advance so rapidly. as we look at the map they're predominantly sunni areas shlgt and he asked that we not disclose thinks identity, but his unit was sunni as well, and as i.s.i.s. was advancing, they got a goal to pull back to brig dade headquarters, he said by the time they got there, i.s.i.s. had already taken over. and now in i.s.i.s.'s hands are humvees purchased from the americans, to mortar rounds, heavy weaponry. this is a pane we've been seeing repeated throughout as i.s.i.s.