So basically long story short we have an inter-party conflict where a guy has cut off a limb of another character and is meta gaming to kill two other players. Then, he got involved in the decision of a element ring, which is legendary, even though he did not involve himself in the fight and actively avoided it. This lead to an other player having to fight a dragon by themselves. Then when he made it clear he was getting involved, another player tried to shot him for 1d8 damaged to distract him. He freaked out and started to shout and hit stuff. We were going to carry on the session for another fight but this just turned everyone's moods off. Any advice in how to deal with this player cause this isn't the first time and means our party is tip toeing around him.