By DAN SEWELL and JOHN MINCHILLO, Associated Press DAYTON, Ohio (AP) — A masked gunman in body armor opened fire early Sunday in a popular entertainment district in Dayton, Ohio, killing nine people, including his sister, and wounding dozens before he was quickly slain by police, officials said. Connor Betts, 24, was armed with a .223-caliber rifle with magazines capable of holding at least 100 rounds