Militants Behead 3 Kurd Hostages in Iraq BAGHDAD, Iraq - Militants beheaded three hostages said to be Iraqi Kurd militiamen, showing their deaths in a video posted on a Web site Sunday and denouncing Kurdish political parties for cooperating with Americans in Iraq.    In a separate incident, a group claimed to have kidnapped 25 members of the Iraqi National Guard, and a report on the Arabic station Al-Jazeera said the soldiers were threatened with death unless a detained Shiite leader is freed within 48 hours...