There were three shots fired, it appears. Two out of the sawed off shotgun, and one from the defender. But after looking at the film it appears possible the shooter shot himself. The possibility of that depends on how many rounds his sawed off shotgun could hold. But unless he had more ammo or more guns, he could not expect to get very far as he moved further into the sanctuary building. So it may well have been a murder-suicide mission. I am a little disappointed that someone dressed like that, with a huge overcoat that could conceal things, would have been allowed to stand against the side wall unmolested for even a few seconds. How did he even get in with an outfit like that? Without being searched?
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Reason i say this is because there is a bright flash against the wall where the gunman was standing, just as he fell. So it appears his shotgun was fired a third time. On the other hand, it's also possible the defender shot simultaneously at the same time and hit. So both might be true. It's also possible the defenders shot caused the gunman to pull the trigger a third time on his shotgun, not aiming at himself.
