Valmiki Ramayana Yuddha Kanda Sarga 75 Shloka 25
Original Shlokaतत्रचाग्निपरीतानिनिपेतुर्भवनान्यपि । वज्रिवज्रहतानीवशिखराणिमहागिरेः ।।6.75.25।।
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तत्र there, अग्निपरीतानि peaks of mountains burnt, भवनान्यपि mansions, वज्रिवज्रहतानि like struck by thunderbolt, महागिरेः huge mountain, शिखराणीव like peaks, निपेतुः fell.
Like peaks of mountains struck by thunderbolt the mansions also fell, caught in fire.