How do I legally and practically remove my father from interacting and believing scammers and get him the medical help he needs?

My father has repeatedly become the victim of scam artists and continues to believe the tales and promises of scammers over his family, friends and formerly trusted professionals. He is making life difficult for his wife and every around him.

After his last encounter, we were able to stop the scammers contacts by several technical means. However, these technical capabilities severely interfered with his privacy and means of conducting his own affairs.

My brother and I have Power of Attorney rights and have used them to 'stop things' in the past. But now my father is again in contact with the scammers.

After having the restrictive technical means in effect for a period of time, my father became increasingly hostile. Since the scamming had seemed to stop, we returned things to a mostly normal level and things were ok for approx 6 months. Now the difficult times have returned.

My question is how to legally and practically remove my father from the scammers grasp and get him the medical help he may need. He is hostile to everyone around him and won't allow our input or assistance.