Violence between warring Palestinian factions claimed the lives of a gunman and four bystanders Sunday night. In the southern Gaza city of Khan Younis, forces loyal to Fatah fought the new Hamas militia, security officials said. A 20-year-old woman, eight months pregnant, was killed when masked gunmen opened fire on a car carrying her and two Hamas operatives, who were wounded. One later died. Gunmen from the two rival Palestinian factions then battled in Gaza City, security officials said, and three bystanders were killed. Relatives of the dead gathered at the hospital where the bodies were taken and shouted anti-Hamas slogans.