The Ashy Woodswallow (Scientific name: Artamus fuscus), sometimes also called the Ashy Swallow-shrike is a woodswallow which is found in south Asia. Like other woodswallows, it has a short curved bill, a short square tail and long wings. It is usually seen perched in groups, high on powerlines, tall bare trees and most often in areas with a predominance of tall palm trees. (Source: Wiki). I found this one on the powerline at the village we stayed. Clicked at Sunderbans in Jan/2018.