Valmiki Ramayana Aranya Kanda Sarga 43 Shloka 39
Original Shlokaउत्थाय बहवो येन मृगयायां जनाधिपाः। निहताः परमेष्वासास्तस्माद्वध्यस्त्वयं मृगः।।3.43.39।।
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येन since, उत्थाय after rising, मृगयायाम् during hunting expedition, बहवः many, परमेष्वासाः great archers, जनाधिपाः kings, निहताः killed, तस्मात् therefore, मृगः deer, वध्यः तु should be killed.
Many kings who were great archers who set out on hunting expedition were killed by him. Therefore, this animal deserves to be killed.