Israeli Airstrike Kills Hamas Founder By IBRAHIM BARZAK, Associated Press Writer GAZA CITY, Gaza Strip - Sheik Ahmed Yassin, the founder and leader of the Hamas militant group that targeted Israelis in suicide bombings, was killed by missiles fired from Israeli helicopters as he left a mosque at daybreak Monday, witnesses said. AP Photo AP Photo Slideshow: Mideast Conflict Hamas confirmed the death in an announcement broadcast over mosque loudspeakers and vowed revenge against Israeli Prime Minister Ariel Sharon (news - web sites). Witnesses said Israeli helicopters fired three missiles at the wheelchair-bound Yassin and two bodyguards as they left...