The officials of GST department had conducted arches at 25 places belonging to owners of four major brick kiln units at ChinnaThadagam and its nearby areas, in Coimbatore district. The search continued for 10 hours. Sources said that quantum is ascertained and it can run up to a few crores. Joint commissioner of GST and Central Excise, VK Vamshadhara said that many brick kiln units have not taken registration under GST.