Mbh 14.76.1b

That prince of elephants possessed of beauty (of form), thus impeded by Arjuna, stopped in its course, with body pierced with many an arrow, like a porcupine with its quills erect. Seeing his elephant impeded in its course, the royal son of Bhagadatta, deprived of sense by rage, shot many whetted arrows at Arjuna. The mighty-armed Arjuna baffled all those arrows with many foe-slaying shafts of his. The feat seemed to be exceedingly wonderful. Once more the king of the Pragjyotishas, inflamed with ire, forcibly urged his elephant, which resembled a mountain, at Arjuna. Beholding the beast once more advancing towards him, Arjuna shot with great strength a shaft at it that resembled a veritable flame of fire. Struck deeply in the very vitals, O king, by the son of Pandu, the beast suddenly fell down on the Earth like a mountain summit loosened by a thunder-bolt. Struck with Dhananjaya's shaft, the elephant, as it lay on the Earth, looked like a huge mountain cliff lying on the ground, loosened by the bolt of Indra. When the elephant of Vajradatta was prostrated on the ground, the son of Pandu, addressing the king who had fallen down with his beast, said,--"Do not fear. Indeed, Yudhishthira of mighty energy said unto me while commissioning me for this task even these words,--'Thou shouldst not, O Dhananjaya, slay those kings (who may encounter thee in battle). O tiger among men, thou shouldst regard thy task as accomplished if only thou disablest those hostile kings. Thou shouldst not also, O Dhananjaya, slay the warriors of those kings who may come forth to fight thee, with all their kinsmen and friends. They should be requested to come to the horse-sacrifice of Yudhishthira.'--Having heard these commands of my brother, I shall not slay thee, O king. Rise up; let no fear be thine; return to thy city safe and sound, O lord of Earth.