"This falls neatly into place if we equate proto-Harappan with Indo-Iranian: the idea of a fire cult was taken along by the emigrating Iranians, while the Indo-Aryans stayed on in the Indus-Saraswati region to develop their altars’ distinct Indian style of construction.... At any rate, how deeply had these Aryan fire-worshippers not penetrated the Harappan civilization, that they had installed their altars in patrician mansions of three of the largest Harappan cities, all three moreover very far from the northwestern border? Indeed, in the Harappan cities on the Indus itself, to my knowledge at least, no such fire-altars have yet been found; if they were imported from outside, it seems they came from the east, which would bring us back to Shrikant Talageri’s thesis that IE originated in the Ganga basin and entered the Harappan area from there. Leaving aside this question of ultimate origins, the very fact of the Vedic fire-altars in the Indus-Saraswati culture is a serious problem for the AIT."