ŚB 10.44.38

तं सम्परेतं विचकर्ष भूमौहरिर्यथेभं जगतो विपश्यत: । हाहेति शब्द: सुमहांस्तदाभू-दुदीरित: सर्वजनैर्नरेन्द्र ॥ ३८ ॥
taṁ samparetaṁ vicakarṣa bhūmau
harir yathebhaṁ jagato vipaśyataḥ
hā heti śabdaḥ su-mahāṁs tadābhūd
udīritaḥ sarva-janair narendra

Synonyms

tamhim; samparetamdead; vicakarṣadragged; bhūmaualong the ground; hariḥa lion; yathāas; ibhaman elephant; jagataḥall the people; vipaśyataḥas they looked on; iti“Oh, oh!”; śabdaḥthe sound; su-mahānmighty; tadāthen; abhūtarose; udīritaḥspoken; sarva-janaiḥby all the people; nara-indraO ruler of men (King Parīkṣit).

Translation

As a lion drags a dead elephant, the Lord then dragged Kaṁsa’s dead body along the ground in full view of everyone present. O King, all the people in the arena tumultuously cried out, “Oh! Oh!”

Purport

Śrīla Viśvanātha Cakravartī explains that many people in the audience thought Kaṁsa had simply been knocked unconscious when thrown from the lofty dais. Therefore Lord Kṛṣṇa dragged his corpse so everyone would realize that the evil King was indeed dead. Thus the exclamation hā hā indicates how surprised the people were that the King was suddenly dead and gone.
The audience’s astonishment is also mentioned in the Viṣṇu Purāṇa:
tato hāhā-kṛtaṁ sarvam
āsīt tad-raṅga-maṇḍalam
avajñayā hataṁ dṛṣṭvā
kṛṣṇena mathureśvaram
“Then the entire arena became filled with cries of astonishment as the people saw that the master of Mathurā had been contemptuously killed by Kṛṣṇa.”