Sunan an-Nasa'i 4115
سنن النسائي#4115SahihIt was narrated that Jundab bin 'Abdullah said:"The Messenger of Allah [SAW] said: 'Whoever fights for a cause that is not clear, advocating tribalism, getting angry for the sake of tribalism, then he has died a death of Jahiliyyah
Scholarly Authentication
We show the most cautious grade (weakest-wins) as the overall label. Individual scholars graded it as follows:
Abu GhuddahSahih
Al-AlbaniSahih
Zubair Ali ZaiSahih Muslim
In-book reference: 37:150