Valmiki Ramayana Yuddha Kanda Sarga 69 Shloka 59
Original Shlokaनिजघ्नुश्शैलशूलार्स्सैर्भिभिदुश्चपरस्परम् ।।6.69.59।। सिंहनादान्विनेदुश्चरणेराक्षसावानराः ।
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रणे in the battlefield, वानरराक्षसा Vanaras and Rakshasas, शैलशूलान् with rocks and swords, परस्परम् one another, बिभुदुः struck, सिंहनादैः lion roar, विनेदुश्च emitted, निजघ्नु one another (with their head).
In the battlefield both Vanaras and Rakshasas struck at one another with their head, rocks and swords and emitted lion roar.