Markandeyapurana 5.1

5.1

pakṣiṇa ūcuḥ
tvaṣṭṛputre hate pūrvaṃ brahmannindrasya tejasaḥ /
brahmahatyābhibhūtasya parā hānirajāyata //

The birds spoke:
“Of old, O brahman! when the son of Tvaṣṭṛ was slain, Indra’s splendour, oppressed by the brahmanicide, suffered a grievous decline. Then because of his wrong conduct Indra’s splendour entered Dharma; and, his righteousness and splendour being gone, Indra became splendourless.