CBI sources said a team of its sleuths were conducting searches at the Sanchar Bhawan in New Delhi after registering a case in this connection last evening.
The sources said that all records pertaining to the allocation of spectrum to new players in January 2008 will be taken to see if there were irregularities in the process.
None of the DoT official was available for comments.
In 2008, eight new players were given licences along with bundled 4.4 MHz spectrum to start mobile services.
The telecom ministry had come under attack for doling out spectrum very cheap compared to its actual market value. 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 huge premium within days of getting the licences.
The government had given telecom licence along with start up spectrum at Rs 1,651 crore (Rs 16.51 billion) for pan-Indian services.
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