"Nizamu-d din Ahmad mentions no other event of Ibrahim's reign but the following : " The Sultan turned his face towards Hindustan, and conquered many towns and forts, and amongst them was a city exceedingly populous, inhabited by a tribe of Khurasani descent, whom Afrasiyab had expelled from their native country. It was so completely reduced by the power and perseverance of the Sultan, that he took away no less than 100,000 captives." ... There is, therefore, no improbability that the independent tribe which had been expelled by Afrasiyab, and practised their own peculiar rites, and whom Ibrahim the Ghazni- vide attacked in a.d. 1079, were a colony of fire-worshippers from Iran."