Mbh 3.203.1a

“Markandeya said, ‘The illustrious Dhundhu, O king, was the son of Madhu and Kaitabha, and possessed of great energy and prowess, he underwent ascetic penances of great austerity and he stood erect on one leg and reduced his body to a mass of only veins and arteries, and Brahma, gratified with him, gave him a boon. And the boon he had asked of the lord Prajapati was in these words, ‘Let no one among the gods, the Danavas, the Rakshas, the Snakes, the Gandharvas and the Rakshasas be capable of slaying me. Even this is the boon that I ask of thee.’ And the Grandsire replied unto him saying, ‘Let it be as thou wishest. Go thy way.’ And thus addressed by the Grandsire, the Danava placed the feet of the Deity on his head and having thus touched with reverence the Deity’s feet he went away and possessed of mighty energy and prowess. Dhundhu, having obtained the boon hastily approached Vishnu remembering the death of his father at the hands of that Deity, and the wrathful Dhundhu having vanquished the gods with the Gandharvas began to distress all the celestials with Vishnu at their head. And at last O bull of the Bharata race, that wicked souled Asura arriving at a sea of sands known by the name of Ujjalaka, began to distress to the utmost of his might the asylum of Utanka. And endued with fierce energy, Dhundhu, the son of Madhu and Kaitabha, lay in his subterranean cave underneath the sands in the observance of fierce ascetic and severe austerities with the object of destroying the triple world, and while the Asura lay breathing near the asylum of Utanka that Rishi possessed of the splendour of fire, king Kualaswa with his troops, accompanied by the Brahmana Utanka, as also by all his sons set out for that region, O bull of the Bharata race!