Matsyapurana 163.20

163.20

na ca taṃ cālayāmāsur daityaughā devasattamam
bhīmavego 'calaśreṣṭhaṃ samudra iva mandaram //

Afterwards Narasiṁha with a loud roar tore up the demons as wind does with the leaves, when the chief Daityas flew up to the sky and showered rocks from there and the whole space became full of them and they fell on the head of Narasiṁha and gleamed like so many fireflies. Then the demons covered Narasiṁha with the rocks as the mountains are covered with rain. But even then the demons could not move Narasiṁha as the violent ocean cannot move the Mandarâchala mountain.—16-20