A policeman stands guard near the scene of mass shooting in Dayton of Ohio, the United States, on Aug. 4, 2019. Local police on Sunday identified the suspect of a shooting spree in the city of Dayton, U.S. state of Ohio, as Connor Betts, a 24-year-old white male. In a press conference, Dayton Mayor Nan Whaley said it took less than a minute for the shooter to claim the lives of nine people, including Betts' 22-year-old sister Megan Betts, before being killed by the police. (Xinhua/Liu Jie)