In Eastern Bengal, members of the Dom ethnic group were trappers and hunters, as well as manufacturing mats, baskets and drums in the towns and on occasion acting as undertakers. As Hindus, the principal festival of the Doms was the Sravannia Puja, during which pigs were sacrificed and their blood mixed with milk and spirits offered to the deity. Doms are usually segregated from the mainstream community as outcastes.
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Source: British Library (bl.uk)