In The Name of Allaah, The Most Merciful, The Bestower of Mercy
Four thousand Khawaarij were fought against by Ali, Ameerul Mumineen [radiyallaahu-anhu] at Nahrawaan and none of them survived except nine. Two men from them departed to Sijistaan and through them appeared the Khawaarij of Sijstaan; two men from them departed to Yemen and through them appeared the Ibaadiyyah of Yemen; two men from them departed to Oman and through them appeared the Khawaarij of Oman; two men from them departed towards other regions of the Arabian Peninsula and through them appeared the Khawaarij of those regions. And a man from them departed to Syria. This was one of the reasons behind their settlement in different lands, then thereafter they became different murderous sects upon divergent creeds.
[Source: Al-Firaq Baynal Firaq’ page 80. Abridged & slightly paraphrased]