Valmiki Ramayana Yuddha Kanda Sarga 29 Shloka 27
Original Shlokaविभीषणेनतत्रस्थानिगृहीतायदृच्छया । शार्दूलोग्राहितस्त्वेकःपापोऽयमितिराक्षसः ।।6.29.27।।
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यदृच्छया by chance, तत्रस्था , विभीषणेन by Vibheeshana, निगृहीता seized, आयम् them, राक्षस the Rakshasas, पापा evil one, इतिएक thus alone, शार्दूलःतु you Saardula, ग्राहित caught hold.
By chance Vibheeshana seized Saardula, the evil Rakshasa who was moving in that army.