as soon as i saw him draw the gun the way he did, it was just instant reaction. >> drop the gun! [ gunshots ] >> shots fired. >> he eventually dropped to his knees. and we tried to direct him to throw the gun away so we could approach him. >> drop the gun! he's still got the gun, dean. drop the gun! the suspect was still armed. you okay? he was still moving. and he still had the gun pointed down towards officer mcginniss. >> the gunman is down, but he isn't dead. and as day turns to dusk, backup arrives and disarms him. he dies shortly after on scene. >> he had a blood alcohol of 18. that's roughly double what would be legal in missouri.