Ernest Walker leads other protestors at a rally in downtown Dallas on Thursday, July 7, 2016. Dallas protestors rallied in the aftermath of the killing of Alton Sterling by police officers in Baton Rouge, La., and Philando Castile, who was killed by police less than 48 hours later in Minnesota.
Ernest Walker leads other protestors at a rally in downtown Dallas on Thursday, July 7, 2016. Dallas protestors rallied in the aftermath of the killing of Alton Sterling by police officers in Baton Rouge, La., and Philando Castile, who was killed by police less than 48 hours later in Minnesota. Smiley N. Pool Dallas Morning News
Ernest Walker leads other protestors at a rally in downtown Dallas on Thursday, July 7, 2016. Dallas protestors rallied in the aftermath of the killing of Alton Sterling by police officers in Baton Rouge, La., and Philando Castile, who was killed by police less than 48 hours later in Minnesota. Smiley N. Pool Dallas Morning News

Police ambushed in Dallas: How the night unfolded

July 08, 2016 1:46 AM