سنن النسائي

It was narrated that Abu Hurairah said: "The Messenger of Allah (ﷺ) [SAW] said: 'Whoever parts from obedience, and splits away from the Jama'ah and dies, then he has died a death of Jahiliyyah. Whoever rebels against my Ummah, killing good and evil people alike, and does not try to avoid killing the believers, and does not pay attention to those who are under a covenant, then he is not of me. Whoever fights for a cause that is not clear, advocating tribalism, getting angry for the sake of tribalism, and he is killed, then he has died a death of Jahiliyyah.'"