Srimad-Bhagavatam: Canto 6 - Chapter 1 - Verse 26
Sanskrit:
दोर्भ्यामुत्कृत्तमूलाभ्यां बभौ रक्तस्रवोऽसुर: ।छिन्नपक्षो यथा गोत्र: खाद्भ्रष्टो वज्रिणा हत: ॥ २६ ॥
ITRANS:
dorbhyām utkṛtta-mūlābhyāṁbabhau rakta-sravo ’suraḥchinna-pakṣo yathā gotraḥkhād bhraṣṭo vajriṇā hataḥ
Translation:
Vṛtrāsura, bleeding profusely, his two arms cut off at their roots, looked very beautiful, like a flying mountain whose wings have been cut to pieces by Indra.
Purport:
It appears from the statement of this verse that sometimes there are flying mountains and that their wings are cut by the thunderbolt of Indra. Vṛtrāsura’s huge body resembled such a mountain.