Valmiki Ramayana Yuddha Kanda Sarga 91 Shloka 84
Original Shlokaयथास्तङ्गतआदित्येनावतिष्ठन्तिरश्मयः । तथातस्मिन्निपतितेराक्षसास्तेगतादिशः ।।6.91.84।।
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आदित्ये sun, अस्तङ्गते when set in the sky, रश्मयः evening, यथा so, नावतिष्ठन्ति rays goes away, तथा in the same way, तस्मिन् him, निपतिते fallen, तेराक्षसाः those Rakshasas, दिशःdirections, गताःwent
Just as Sun rays go away as soon as the Sun sets in the evening, the Rakshasas also went in all directions seeing Indrajith fallen.