Valmiki Ramayana Yuddha Kanda Sarga 50 Shloka 37
Original Shlokaतमागतमभिप्रेक्ष्यनागास्तेसम्प्रदुद्रुवुः । यैस्तौसत्पुरुषौबद्धौशरभूतैर्महाबलौ ।।6.50.37।।
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शरभूतैः in the form of arrows, महाबलौ mighty, यैः those, तौ both, सत्परुषौ noble, बद्धौ bound, ते those, नागाः serpents, आगतम् seeing, तम् they, प्रेक्ष्य seeing, सम्प्रदुद्रुवुः fled.
Seeing the noble Rama and Lakshmana bound by the serpents in the form of arrows (released by Indrajith), the serpents fled.