You’re sure its AK not AX? Or just betting it is? I haven't seen the arm, so I don't know.
However, it's not uncommon to misread letters. None of my searches for "Ismail Ax" turned up anything convincing. So, I tried "Ismail Ak" and voila. Don't know what it means. Weird coincidence?!
Very weird coincidence I think. Unless the perp traveled to Turkey. On some other thread a picture taken in Indonesia shows a smiling fellow with a name almost identical to Cho’s. Could be our perp traveled to some muslim countries recently. Seems a long way to go to see a shrink.