>> This person obviously had some delusion. This person also was very committed to killing officers.>> The military veteran who fatally shot five police officers in Dallas last week asked authorities how many people he'd shot and said that he wanted to kill more. That's according to Police Chief, David Brown, who on Monday said he and his family had received death threats almost immediately after the attack, and defended the decision to send in a robotic bomb that took out 25 year old Micah Johnson after an hours long standoff.
>> This wasn't an ethical dilemma for me. I'd do it again.>> Reuters' Erie Sheyder is covering the story in Dallas.>> The Chief added that on the night of the attack, he decided rather quickly to use a bomb attached to a robot. His only stipulation was that his officers did not bring the building down.
>> Thursday's attack came at the end of an otherwise peaceful demonstration against the killings of two black men by police in Baton Rouge, LA and suburban Minneapolis. Johnson told negotiators he'd been angered by those deaths and wanted to kill white people. Police Chief Brown said that explosives found at Johnson's home indicate that he was planning a larger scale attack.
>> There was a large stockpile. One of the bomb techs called me at home to describe his concern of how large a stockpile of bomb making materials he had. And according to that bomb tech he knew what he was doing. That this wasn't some novice.>> Investigators are still trying to understand why Johnson wrote the initials RB in his own blood in two locations of the building where he was cornered.
Nine other officers were also injured in the siege. President Barack Obama is expected to speak at a memorial service for those who died on Tuesday.