The CBI has filed a chargesheet against Manoj Modi, a top lieutenant of Reliance Industries Chairman Mukesh Ambani, and five others in a case relating to masking of international calls as local, causing huge revenue loss to the government.

The chargesheet was filed in a local court in Chennai, four years after CBI took up investigation and five years after Reliance Infocomm paid Rs 150 crore towards penalty imposed by telecom tribunal TDSAT, a source said today.

Besides Modi, CBI named Akhil Gupta, Shankar Adawal, Pankaj Panwar, K R Raju and Bhagwan Das Khurana of Reliance Infocomm Ltd in the chargesheet.

Incidentally, the company, minus any of these officials, is now controlled by Mukesh's younger brother Anil who got it as part of the division of the Reliance empire and it has since been renamed as Reliance Communications.

Khurana had for a while joined Anil Ambani group, while Gupta is now heading a leading US private equity firm, Blackstone.

CBI filed the chargesheet earlier this week in the court of Additional Chief Metropolitan Magistrate, Egmore, Chennai, under 120-B (criminal conspiracy), 20-A (breach of licence), 21 (unauthorised telegrapg) and 25-C (intentionally damaging or tampering with telegraphs) of the Indian Telegraph Act.

Besides, sections 65 (tampering with computer source documents), 66 (hacking with computer system), 85 (contravention of any of the provisions) of the Information Technology Act.

The case relates to manipulation and tampering of calling lines identification of ISD calls by Reliance Infocomm Ltd and thereby, passing off international calls as local ones and causing loss to the government and its PSUs, BSNL and MTNL, to the tune of several crores of rupees.

According to the CBI, the company would mask incoming international calls as local ones through one of the three gateways-Chennai, Kolkata and Mumbai. The calls would be put on the Public System Telephone Network as local. This was done, CBI sources said, with the help of specially designed software and accomplices in BSNL.

This was allegedly done to avoid paying Access Deficit Charges (ADC) to PSU, BSNL. Private telecom operators have to pay the state-owned telecom behemoth Rs 4 on every incoming international call as ADC.

When contacted, a RIL spokesperson said: "We are not aware of any such development."

It may be recalled that RIL last month re-entered the telecom arena through acquisition of Infotel, an internet service provider that acquired pan-India Broadband licence and Modi is believed to be the brain behind the venture.

Modi was formerly director of Reliance Infocomm, Gupta, the then CEO, Shankar, the then head of the company's corporate affairs, and Panwar, the then head regulator of the company.