Deadly terrorist sect, ISIS have beheaded four Kurdish Peshmerga fighters in 'revenge' for a raid by US special forces that rescued 70 Iraqi hostages and killed 20 terrorists. In the photos, a masked English-speaking man with an American accent is seen clutching a knife as he stands over one of the hostages. Three other jihadis - all dressed in black with their faces covered - are also seen holding blades as they stand behind three other Kurds wearing orange jumpsuits. Addressing President Obama, the lead executioner says the beheadings are 'revenge' for the raid on an ISIS jail. See more photos…