Valmiki Ramayana Yuddha Kanda Sarga 75 Shloka 63
Original Shlokaतथैवापततांतेषांकपीनामसिभिशशितैः ।।6.75.63।। शिरांसिसहसाजह्रूराक्षसाभीमदर्शना ।
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तथैव in that manner, दर्शना showed up, राक्षसाः Rakshasas, आपतताम् approaching, तेषांकपीनाम् those monkeys, शिरांसि head, सहसा instantly, शितैः sharp swords, जह्रुः cut off.
When the Rakshasas showed up in that manner, the monkeys approaching them cut off their heads instantly with sharp swords.