ebel a member of the white supremacist prison gang called the 211 crew. abc news learned in the month before he died, tom clements thought the gang was too strong and to break it up he ordered members sent to different institutions. investigators are interviewing inmates to see if the gang ordered a hit on clements. in recent years, experts say ultraviolent white supremacist prison gangs like the 211 crew and the much larger aryan brotherhood, the subject of the national geographic investigation, have expanded their criminal enterprises outside the prison walls, selling drugs and running guns, all directed from behind bars. they devised all kinds of codes, so they might send out a letter that looks like a benign letter but is actually direct a hit or some kind of criminal activity. reporter: still, experts say it is extremely rare for prison gangs to kill top officials because to do so means all-out war. war may well be what the 211