This is a developing story. Last updated 9:12 a.m. ET.
Snipers shot and killed five Dallas law enforcement officers and injured another seven at the end of a rally in downtown Dallas, where hundreds were protesting police shootings that happened in other parts of the country earlier this week.
Four of the slain officers worked for Dallas Police; the fifth was identified as 43-year-old transit officer Brent Thompson, of Dallas Area Rapid Transit, or DART.