A trauma surgeon at Parkland Memorial Hospital who is black says he understands the "anger and frustration and distrust of law enforcement."

Dr. Brian H. Williams went on to say Monday that police are not the problem, but instead it's the lack of discussion about "the impact of race relations."

Williams and other doctors held a news conference to discuss the aftermath of Thursday night's shooting.

Five officers died and nine officers and two civilians were injured during a downtown Dallas protest over recent fatal shootings by police.

Williams said that not being able to save some of the officers "weighs on my mind constantly."