Srimad-Bhagavatam: Canto 9 - Chapter 1 - Verse 31


यो वै हरिश्चन्द्रमखे विक्रीत: पुरुष: पशु: ।स्तुत्वा देवान् प्रजेशादीन् मुमुचे पाशबन्धनात् ॥ ३१ ॥


yo vai hariścandra-makhevikrītaḥ puruṣaḥ paśuḥstutvā devān prajeśādīnmumuce pāśa-bandhanāt


Śunaḥśepha’s father sold Śunaḥśepha to be sacrificed as a man-animal in the yajña of King Hariścandra. When Śunaḥśepha was brought into the sacrificial arena, he prayed to the demigods for release and was released by their mercy.


Here is a description of Śunaḥśepha. When Hariścandra was to sacrifice his son Rohita, Rohita arranged to save his own life by purchasing Śunaḥśepha from Śunaḥśepha’s father to be sacrificed in the yajña. Śunaḥśepha was sold to Mahārāja Hariścandra because he was the middle son, between the oldest and the youngest. It appears that the sacrifice of a man as an animal in yajña has been practiced for a very long time.