The three hostages killed by Israeli forces in Gaza were carrying a makeshift white flag when a soldier felt threatened and opened fire, a senior Israeli military official said Saturday, adding that an investigation was underway and the killings were “against our rules of engagement.” The deaths have sparked outrage and protests in Israel, with a group representing families of hostages meeting urgently to discuss ways to raise pressure on Israeli leaders to secure the release of all hostages taken in the Oct. 7 attack by Hamas.