Valmiki Ramayana Yuddha Kanda Sarga 67 Shloka 23
Original Shlokaतदापतन्तंसम्प्रेक्ष्यमुष्टिनाभिजघान ह । मुष्टिप्रहाराभिहतंतच्छैलाग्रंव्यशीर्यत ।।6.67.23।। सविस्फुलिंगंसज्वालनिपपातमहेतले ।
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तदा after that, आपतन्तम् coming towards, सम्प्रेक्ष्य observing, मुष्टिना with fist, अभिजघान ह pierced, मुष्टिप्रहाराभिहतम् struck by fist, तत् that, शैलाग्रम् mountain peak, व्यशीर्यत broken, सविस्फुलिंगम् like sparks of fire, सज्वालम् shining brightly, महीतले on the ground, निपपात fell.
(Kumbhakarna) observing the mountain peak coming towards him pierced it with his fist. Struck by the fist, the peak broke and sparks of fire came out shining brightly and fell on the ground.