The Income Tax Department has detected unaccounted income of about Rs 100 crore after it recently raided a Kolkata-based group engaged in manufacture of TMT bars and construction material, the CBDT said on Monday.

The searches were carried out on December 1 at over 20 premises linked to the unidentified group in West Bengal and Odisha.

A number of "incriminating" evidences in the form of documents and digital data demonstrating high-value unaccounted cash payments, unaccounted cash purchase and sales, suppression of production, etc. have been seized, the Central Board of Direct Taxes (CBDT) said in a statement.

The policy-making body of the income tax department said preliminary analysis of these evidences found that many paper or shell companies are run by the group to provide accommodation entries (bogus entries) to its flagship concerns.

"These shell entities were found to have routed back their unaccounted money in the guise of share capital/unsecured loan into books of account.

"Such modus operandi has been admitted by one of the key persons of the group," it claimed.

The CBDT said Rs 75 lakh cash and jewellery valued at Rs 2.26 crore was seized while some bank lockers were put under restraint.

"The search action, so far, has led to the detection of total unaccounted income of around Rs 100 crore," the CBDT said.