The Income Tax department has launched a probe against a number of political parties as well as charitable and religious trusts after it found that they were receiving "huge funds" beyond the exemption cap for filing tax returns.

The department has compiled a list of those non-filers of I-T returns who are exempted to pay tax up to a certain limit of funds under Section 139 of the Income Tax Act.

Political parties, a variety of charitable organisations, scientific research associations, educational institutes and certain hospitals have been found to have "huge receipts" of funds by way of donations, contributions and payments in an I-T analysis report.

According to the report, a number of organisations under this exempted category are "potential assesses" but the I-T could not scrutinise their accounts as they do not file returns as mandated under the Act.

"Any such exempted organisation has to file I-T return if it exceeds the threshold of income that was set for the charitable organisation category. But many institutions are not doing so," sources privy to the development said.

An earlier I-T probe had found that close to 300 registered political parties in the country had never filed their tax returns, which they should be doing as they receive large donations from a host of contributors, they said.

"By scrutinising these returns and donations, not only the organisation which is violating the exemption norms could be checked, but also the department will get to know the people who are making undercover donations," I-T sources said.

The department has already begun an exercise asking its exemptions directorates across the country to track such bodies and develop actionable information about the source and quantity of funds received by them.

"The enforcement units of the department have been asked to check non-filers of returns categories to look for possible cases of tax evasion," a senior I-T official said. (PTI)