According to CBI, the searches were conducted at the premises of Raja, R K Chandolia, his former personal secretary, Siddhartha Behuria, the former secretary of department of telecommunication and K K Sridhar, the then member of the telecom commission, DoT.
The premises of A K Srivastava, the former deputy director general, access service wing, DoT and Sadiq Basha, managing director of a Chennai-based export firm were also searched in an ongoing investigation relating to irregularities in allotment of unified access service licences, a CBI official said.
"Searches conducted so far at around 14 places have yielded recovery of incriminating documents," said Vineeta Thakur, deputy inspector general and spokesperson of CBI, adding that the searches are still going on.
The CBI had earlier registered a case on October 21, 2009 against unknown officials of the DoT and unknown private persons or companies and others under section of the IPC and Prevention of Corruption Act.
"It has been alleged that there had been serious irregularities in the award of unified access service licences to private companies. As per information received, there was criminal conspiracy between certain officials of DoT and private persons or companies and others in order to award licences to these companies by putting a cap on the number of applicants against recommendations of Telecom Regulatory Authority of India and by awarding licences to private companies on first come first serve basis on the rates of 2001 without any competitive bidding," Thakur said.
CBI quizzes Raja's key aide Sadiq Basha
In Chennai, a key aide of Raja, Sadiq Basha, was taken in for questioning by CBI officials who raided his house and the DMK leader's residence at his native Perambalur.
Bank details were sought from Basha and others, CBI the sources said.
CBI officials raided the premises of Raja's relatives including his brother and sister in Chennai and Sri Rangam and Tiruvanaikaval in Tiruchirappalli district.
The residential premises of Raja at his native village Velur in Perambalur, his erstwhile Lok Sabha constituency, and the office of a trust run by his family in the district also came under the CBI scanner.
Sources said the crux of the entire scam was the issue of the first-come-first-served basis for the allocation of spectrum in 2008 after the cut off date for receiving applications was advanced at short notice by a week from October 1, 2007 to September 25.
Several companies complained that they had been unable to fulfill the application requirements because of the very short notice and had alleged that the preponement was clearly aimed at favouring the chosen few who had been intimated beforehand.
Raja quit just before the Winter Session of Parliament began, but it was not enough for the opposition which has been demanding a Joint Parliamentary Committee probe into the 2G scam which has led to virtual wash out of this session.
Wednesday was the 19th consecutive working day when both the Lok Sabha and the Rajya Sabha were disrupted on the JPC demand which the government has refused to accept.