Official sources said the department is likely to file a criminal complaint against Ms Bharti and Mr Kumar.
Criminal complaint is also likely against Mr Lalu Yadav's wife and former Chief Minister Rabri Devi and their son and former deputy Chief Minister Tejashwi Yadav.
The Tax officials said that the criminal complaint will be filed in a Delhi court and they want to question Ms Bharti and her husband again in Delhi.
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