They killed him with a bomb disposal robot.
I remember discussing this on FR at the time of the Dallas shooting and when they thought they had him surrounded in a parking garage, I was thinking a drone would be the best way to locate him without endangering cops, since he was trying to ambush them.
The capability of these lethal drones is here, legislatures are today facing the question of whether cops should be allowed to use them, but the issue seems to be somewhat flying under the radar so to speak.
land air or sea, it’s a drone.