Mahabharata 1.48.12

1.48.12

vasāmedovahāḥ kulyā nāgānāṃ saṃpravartitāḥ |
vavau gandhaśca tumulo dahyatāmaniśaṃ tadā || 12 ||

"When the Ritwiks in that snake-sacrifice began to pour clarified butter into the fire, terrible snakes, striking fear into every creature, began to fall into it. And the fat and the marrow of the snakes thus falling into the fire began to flow in rivers. And the atmosphere was filled with an insufferable stench owing to the incessant burning of the snakes. And incessant also were the cries of the snakes fallen into the fire and those in the air about to fall into it.