Police: Shooter killed 9 in Ohio, including his sister

DAYTON, Ohio -- A gunman in body armor who opened fire early Sunday in a popular entertainment district in Dayton, Ohio, killed nine people, including his sister, and wounded dozens of others before he was quickly slain by police, city officials said.

The 24-year-old shooter was killed by police less than a minute after he started firing a .223-caliber rifle in the streets of Dayton's historic Oregon District about 1 a.m. in the second U.S. mass shooting in less than 24 hours. 

His 22-year-old sister Megan was the youngest of the dead -- all killed in the same area of bars, restaurants and theaters that is considered a safe area downtown, police said.