Via the New York Times:
If there were such a thing, it would probably be rule No. 1 in the teaching manual for instructors of aspiring suicide bombers: Don’t give lessons with live explosives. In what represented a cautionary tale for terrorist teachers, and a cause of dark humor for ordinary Iraqis, a commander at a secluded terrorist training camp north of Baghdad unwittingly used a belt packed with explosives while conducting a demonstration early Monday for a group of militants, killing himself and 21 other members of the Islamic State of Iraq and Syria, army and police officials said. Iraqi citizens have long been accustomed to daily attacks on public markets, mosques, funerals and even children’s soccer games, so they saw the story of the fumbling militants as a dark — and delicious — kind of poetic justice, especially coming amid a protracted surge of violence led by the terrorist group, including a rise in suicide bombings.
Iraqis interviewed in the above-linked story are celebrating the incident.