Complex sentence: Tom refuses to put his gun down saying she will shoot him if he does, Hudson tackles Tom knocking him over, Tom holds Hudson by his neck and Diana knocks him out, Diana holds Hudson not to move or she will pull the trigger.
Split into simpler sentences: Tom refuses to put his gun down saying she will shoot him if he does, Hudson tackles Tom knocking him over, Tom holds Hudson by his neck and Diana knocks him out. Diana tells Hudson not to move or she will pull the trigger.