DALLAS, July 9, 2016 (Xinhua) -- A woman holds a placard during a mourning for the police personnel killed by snipers in Dallas, the United States, July 8, 2016. Five police personnel were killed and seven others injured as two snipers opened fire at them during a protest against police shootings of two African-American men in Louisiana and Minnesota, in downtown Dallas Thursday night. (Xinhua/Tian Dan)