The CBI, which filed a fresh affidavit, said the telephonic conversation between Radia and others were being examined and she would be called for questioning at an appropriate time.
"It should be pointed out that the recordings, which are the main basis of investigation regarding her role, are still being examined. It is only when the materials based on these calls are cross-checked, verified and relevant evidence on matters disclosed by these calls are obtained through investigation, entirety of the material would be put to Radia at an appropriate time," the agency said in its seven-page affidavit.
While admitting that the case in which the FIR was registered against unknown persons in October 2009 is of 'enormous magnitude', the CBI said that the investigation was "not merely confined to India alone, but also has ramifications in various foreign countries."
It also gave the list of companies whose premises were raided and searched during the investigations in different parts of the country.
The companies named in the affidavit are -- Unitech Wireless Pvt Ltd having its branches in different telecom circles, S.Tel Ltd, Shyam Telelinks Ltd, Swan Telecom Pvt Ltd, Datacom Solution Pvt Ltd, Loop Telecom Pvt Ltd, Tata Teleservices Ltd, Allianz Infratech Pvt Ltd, Spice Communication Ltd and Idea Cellular Ltd.
"More than 20 searches have been carried out so far. The searches carried out as well as the seizures made by the CBI have resulted into the retrieval of as many as 866 documents/ files running into about 82,665 pages," the affidavit said.
"The exercise is a prolonged and painstaking one and is still continuing as recordings of 5,851 calls, many of them being 30-40 minutes-long, have to be listened to and analysed," it said, adding about 3,500 calls have been analysed so far.
"It is submitted that investigation of the cases of this mammoth dimension require considerable time to conclude," the CBI affidavit said.
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