Is ISIS running out of suicide bombers? Terror group suffers shortage of martyrs after dozens of fighters desert or defect to rival militias
Dozens of would-be suicide bombers left ISIS before carrying out missions
Terrorists have set up roadblocks and security checks to stop desertions
Anyone guilty of desertion has been told they face summary execution
But the threats have not stopped jihadis defecting to other militant groups or fleeing the battlefield before carrying out their attacks
