Valmiki Ramayana Aranya Kanda Sarga 28 Shloka 9
Original Shlokaशरजालावृतस्सूर्यो न तदा स्म प्रकाशते। अन्योन्यवधसंरम्भादुभयोस्संप्रयुध्यतोः।।3.28.9।।
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अन्योन्यवधसंरम्भात् eager to kill each other, उभयोः both, सम्प्रयुध्यतोः of those waging (fighting), तदा then, शरजालावृतः covered with arrows, सूर्यः Sun, न प्रकाशते स्म not seen.
While they were engaged in the battle, eager to kill each other the sky was covered with arrow and the Sun could not be seen.