All the population of the three worlds was scorched by the combined heat of the weapons. Everyone was reminded of the sāṁvartaka fire which takes place at the time of annihilation.
Srimad Bhagavata Purana
श्रीमद्भागवतमहापुराणम्
मूल श्लोकः
दृष्ट्वास्त्रतेजस्तु तयोस्त्रींल्लोकान् प्रदहन् महत् । दह्यमानाः प्रजाः सर्वाः सांवर्तकममंसत
dṛṣṭvāstratejastu tayostrīṃllokān pradahan mahat | dahyamānāḥ prajāḥ sarvāḥ sāṃvartakamamaṃsata
SB 1.7.31