Twenty-one Israeli soldiers were killed Monday when they came under attack in the southern Gaza Strip‚ triggering a blast that collapsed two buildings with soldiers inside them‚ the military said Tuesday morning. The buildings were being rigged for demolition by troops when Palestinian gunmen fired an RPG at a tank securing the forces. A second blast then occurred in the buildings‚ possibly as a result of a second RPG‚ leading to their collapse. It was the single deadliest incident since...