Instead of immediately jumping to disciplinary action, try discussing with him about his current situation and see if there's anything you can do to assist him in his struggles.
James has been experiencing a lot of problems in his personal life lately. As a result, he has been in a constant bad mood and would occasionally lash out at his co-workers for little to no reason.
James' aggression has worsened over time. His manager, Joe, contemplates James' termination or suspension for his behaviour. Fellow coworker Alex has a different opinion.
The company and I are here to offer assistance if needed.
Joe calls James to his office and informs him of his misbehaviour, and reminds him they are in a professional environment and James' behaviour is unacceptable and may lead to disciplinary action.
Being confronted by a supervisor and having his career threatened, James responds negatively verbally through his words, para-verbally through his tone and expression and non-verbally through his physical actions and hand gestures.
Noticing James' state of emotional distress, Joe ensures him assistance can be offered. He will also smooth things over with the other coworkers and ensure they understand James' situation if needed. At the same time, Joe emphasizes James' behaviour is not suited for a professional environment and he will face disciplinary action if he does not show improvement.
Depending on how James takes the offer, he can either open up to Joe or keep his privacy. Regardless of his choice, James understands the situation and feels less victimized due to Joe's assurance. James agrees to cooperate.