A routine inspection of biryani restaurants in Hyderabad has unexpectedly exposed what officials now describe as one of the largest suspected tax evasion rackets in the country, with concealed sales estimated at nearly Rs 70,000 crore. What began as a local compliance check has expanded into a nationwide investigation spanning thousands of eateries and multiple states. The probe was initiated after officers of the Income Tax Department noticed inconsistencies in the reported revenues of several popular biryani outlets in Hyderabad. Initial surveys revealed significant gaps between actual customer footfall and the turnover declared in tax filings. These discrepancies prompted a deeper forensic examination of billing practices used by the restaurants, reports said.