(IDEX Online) - Income tax officials investigating a leading diamond manufacturer and exporter in India say they've discovered almost $22m of undisclosed income.It follows a series of searches at 23 premises in Surat, Navsari, Morbi and Wankaner in Gujarat and Mumbai in Maharashtra. The Income Tax Department has not named the company involved.Documents pertaining to unaccounted purchases and sales were seized, along with bogus invoices, paperwork relating to the movement of cash and stock through angadia (courier) firms and the use of unaccounted income to acquire property and stock in the past five years.The Central Board of Direct Taxes (CBDT) said $265,000 of "unaccounted" cash and jewelry worth was seized during the raids, together with 8,900 carats of diamond stock valued at $1.48m.The undisclosed income relates to both diamond transactions and the sale of tiles, which the company also manufactures.