Ok, I owe the FBI agent an apology.
Victim grabbed the barrel of the agents rifle and started pulling. Agent thought he was going to loose control of his weapon and fired.
I did get it right that it was a rifle.
Well, this fact sure puts a whole other perspective on what happened. Dark room, no visibility, you expect the bad guy to put up a fight, and someone grabs your rifle. You don't expect a bound victim to be fighting. What would you do? I read someplace that the FBI specifically decided to breach without any lights. I suspect that the FBI tactics manual is going to get a rewrite.