I was in Terminal 7 waiting for my brother to arrive when we saw the response. Many, many police cars going very fast in the wrong direction on the LAX loop was interesting to watch. I think the most stressful part of it was that we didn't know what was going on at the time, and that my brother's plane was minutes from landing. We were hoping (as we saw several large fire trucks go by) that nothing was wrong with his plane. He landed just fine, maybe 15 or so minutes after the shooting.
It took LA news choppers all of another ten minutes to swarm overhead.
We didn't find out what actually happened until we got home.
Terminal 7 is not the international terminal, but it was still probably the closest I've ever been to an international class incident.