Tightening its noose on BJP MP Anurag Thakur and his brother Arun Singh, both sons of former chief minister PK Dhumal, Vigilance and Anti Corruption Bureau today booked them for alleged cheating and conspiracy in a land case. In the FIR in the land deal, Thakur and Arun Singh have been accused of forging documents in connivance with some revenue officials for purchasing the land of a Dalit, Premu now deceased.