In a communication to Principal Chief Commissioners in 18 regions across the country, the department has asked officers to look into Annual Information Returns (AIR), which do not contain valid PANs.
The database for 'Non-PAN AIR transactions' has already been disseminated to Principal Chief Commissioners based on the regions.
It has also made available list of cases related to penny stock transactions for Assessment Year 2009-10 to 2013-14 for identifying potential black money holders.
Principal Chief Commissioners have also been asked to scrutinise "non-filers" and those who have not submitted their response to the tax authorities about non-filing of returns.
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The department, the communication said, is also developing a new functionality on e-filing portal, which will force the tax payers to own up non-PAN transactions.
According to sources there are around 60 lakh high value AIR transactions without PANs which can be mined through online tracking systems.
The Budget for 2016-17 announced a four-month compliance window, allowing domestic black money holders to declare their unaccounted wealth, by paying a tax and penalty of 45 per cent and escape prosecution and harsher punishment.