The black Muslim and Black Panther stuff is thoroughly intertwined; Essex met with BP members before his bloody rampage (though of course the Black Panthers claim he was never part of their organization).
I'll be toasting John's demise this evening with my best bourbon.
Let's not forget the 1973-74 Zebra Murders in California by Nation of Islam members. While the official count is 16 dead, "some members of the Zebra task force suspected that at least 71 murders throughout California might have been the work of various other Death Angels squads. Since many victims were drawn from the ranks of the homeless or hitchhikers, there is no certainty about the actual numbers".