My guess - sniper tracks the shooter . not sure if he's a threat. i would think it would be difficult to determine if the shooter had a gun or could be a photographer trying to get a different angle. at one point split seconds before the shooter lifts his head from the scope to verify what he thinks he sees. shooting starts as the sniper returns to the weapon and starts shooting at the assassin. I'm suprised he got him because the snipers rifle looks like its moving too much to deliver a kill shot. Maybe the other sniper got him.