UPDATE: 10 Dallas police officers shot, 3 dead

UPDATE 2:
Chief David Brown said the shooters were located in garages. One of the shooters has been identified and police are searching for him. The other suspect is cornered.
UPDATE:
One shooter is negotiating with police. Two of the officer killed were Dallas Police and one was a DART police officer.
ORIGINAL POST:
Ten Dallas police officers were shot and three killed by what was described as two snipers at a demonstration for two black men shot by officers in Baton Rouge and Minneapolis. Three officers are in critical condition.
The demonstration was peaceful.
Attorney Pete Schulte, who was on the scene, told Channel 11 News the attack had to have been planned based on the precision of the attack.
The shootings were near El Centro College. The officers were taken to Baylor Hospital.