Just report to the police, if its just a regular argument then police would of cuz ignore it but if it involve gangsters then the police could do something. Even if they dont do anything, at least they have a record of ur report and if anything happen to u or ur father then he will be in deep shit.

Forget about sentiment/brotherhood/family since he dont even value any of that why should you, safety is more important and if he's causing so much trouble just report that *******.