In one of the biggest recoveries till date, the Income Tax (IT) department has seized Rs 163 crore cash and about 100-kg bullion, following raids at multiple premises of a road construction firm in Tamil Nadu, officials said. The searches were launched on Monday at the premises of Ms SPK and Company, a partnership firm engaged in roads and highways construction on contract from the government.The raids followed after IT officials found "evidence of suspected tax evasion by the firm and its associates". Sources say that those raided have strong political links. Tamil Nadu CM directly oversees the Department of Highways and Minor Ports. Earlier the DMK had alleged that contractor Nagarajan was doing benami business for TN CM.