The Central Bureau of Investigation (CBI), which hopes to complete the probe into the 2G Spectrum case within a year, has roped in the Comptroller and Auditor General (CAG) to help ascertain the alleged financial irregularities in distribution of new licenses and spectra in 2008 at prices fixed in 2001.
CBI Director Ashwani Kumar said in an interview that the case required financial expertise to arrive at a conclusion.
"Investigation is progressing. At the moment, we have requested the Comptroller and Auditor General of India to help us in the financial part of it," Kumar said.
The CBI Director said that the agency expected the investigation to be over within a year.
The CBI had registered a case on October 21, 2009 against unknown Department of Telecom officials and private persons and companies for allegedly causing loss of thousands of crores of rupees to the exchequer.
The Chief Vigilance Commissioner (CVC) had recommended a CBI probe into the procedures followed for selecting companies for giving 2G spectrum.
Eyebrows were raised when two of the new players -- Unitech Wireless Services and Swan Telecom -- sold part of their stake at a huge premium within days of getting the licences.
In 2008, eight new players were given licences along with bundled 4.4 MHz spectrum to start mobile services.
Asked if the agency would question some other people including high-profile corporate lobbyist Neera Radia, who figured in a purported telephonic conversation with a Union Minister over 2G spectrum allocation, Kumar said, "If it is relevant, we will look into it."
The CBI Director said the agency was carrying forward the investigation after the CVC had completed its initial probe into the alleged irregularities.
The CBI had earlier searched offices of Wireless Planning Cell (WPC), the department responsible for allocating spectra, and the office of Deputy Director General (Access Services) of the Telecom Ministry to probe the allegations of connivance of officials with private companies in their allotment.
It had also conducted searches in eight cities housing headquarters of various telecom firms in connection with its probe into the alleged scam.