The Central Bureau of Investigation (CBI) has discovered 15 properties allegedly belonging Haribansh Kumar Chaudhary, a 1988 batch officer of the Indian Revenue Service (IRS), against whom the probe agency had registered a disproportionate assets case.

Documents accessed by DNA suggest that the worth of the officer's assets grew 100 times or more in five years, during which he was posted as Assistant Commissioner of Income Tax and was elevated as Commissioner.

The CBI has booked Chaudhary and his wife after a complaint that the senior officer of the I-T Department's Appeals Division had amassed wealth worth over Rs 4 crore.

CBI sources say that the accused had not only amassed wealth in the form of huge investments but also brought agricultural land in various parts of Delhi. Sources said that the accused built properties, a list of which is with DNA, in the capital as well as his hometown in Bihar. The agency has also dug out 12 demat accounts as well as four shell companies under the names of his family members, including his 85-year-old mother.

Among some of the properties allegedly linked to Chaudhary are agricultural land in New Delhi's Najafgarh tehsil worth about Rs 5.76 crore. The built-up properties include one in Vaishali colony of New Delhi's Dabri area and another one in Mahavir Enclave in village Palam. The first one has been allegedly acquired by the CBI for Rs 39 lakh and the other one at approximately Rs 50 lakh. Another Rs 10 lakh, the CBI said, were spent by the officer on renovating a single-storey building in Saharsa district of Bihar.

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"It is alleged that Mr Choudhary has not intimated his competent authority about the acquisition of properties prior to the check period (January 1, 2010 to October 31, 2015)," CBI sources said.

The source of income for the family has been found out as salary of the accused (Rs 1 crore), income of wife Anupama (Rs 48 lakh), mother (Rs 5 lakh), son (Rs 13 lakh) and income from shares worth Rs 1,49,42,191. The agency stated that expendutire during the period was Rs 33 lakh and savings were Rs 3 crore 81 lakh.

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Sources told DNA that the official allegedly opened four private companies in the name of his family members to route the payoffs. Sources also said that some chartered accountants, based out of Gujarat and Chennai, were part of the alleged criminal activities spread over at least three states.

According to official sources, the names of four real-estate firms have cropped up so far. They include Delhi-based Kanta Realbuild Pvt Ltd, SBM Promoters Pvt Ltd and Chennai-based Interface Estates Pvt Ltd and Interface Holding Pvt Ltd.

Company records suggest that Anupama was elected as the director of the firms on February 10, 2014, October 1, 2013, November 12, 2014 and May 21, 2015, respectively. Agency sources said that the senior I-T official allegedly used the help of two chartered accountants – Bhupendra Habildas Bakaswala and Birji Subashchandra Shah – who are designated as additional directors in these firms.