DAYTON, Ohio – 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 of ammunition and squeezed off dozens of shots before he was gunned down no more than 30 seconds after his rampage began, Police Chief Richard Biehl said. Surveillance video shared by police showed officers shot Betts at the doorstep of further destruction, just stopping him from entering a bar where some people took cover when the chaos broke out around 1 a.m.