India lobbyist Niira Radia's home and offices raided
India's top investigation agency has raided the home and offices of a corporate lobbyist in connection with a corruption inquiry.
The Central Bureau of Investigation searched Niira Radia's farmhouse in south Delhi and business premises.
Ms Radia is said to have had links to A Raja, who quit as telecommunications minister last month after mobile phone licences were allegedly undersold.
The CBI raided his homes in Delhi and Madras this month.
The so-called 2G spectrum inquiry has been described as the country's biggest scandal.
Opposition demands for a cross-party inquiry into the matter paralysed the Indian parliament's winter session, which ended on Monday.
A spokesman for the CBI told the BBC that its detectives had raided 34 homes and offices in Delhi and the southern city of Madras on Wednesday.
They included the home and offices of Ms Radia as well as the home of Pradip Baijal, a former chairman of India's telecoms regulator.
The BBC's Mark Dummett in Delhi says that Ms Radia is the most high-profile target of Wednesday morning's raids.
Last month, copies of Ms Radia's telephone conversations, which were recorded as part of a tax investigation, were leaked to the media.
They included discussions with leading politicians, industrialists and journalists, in which she appeared to be speaking in favour of Mr Raja.
He has been accused of deliberately underselling 2G mobile phone licences in 2008, costing the exchequer billions of dollars.Trial by media
The opposition has accused the police of acting far too slowly to investigate this scandal, details of which first emerged a year ago.
Mr Raja has still not been questioned, although his homes were raided last week, and those of some of his associates were searched on Wednesday morning.
Our correspondent says opposition demands for an inquiry have made this the major political issue in India.
In a court affidavit filed last week, the government said it had begun tapping Ms Radia's phone after an allegation that she was spying for foreign intelligence.
Mr Raja is accused of issuing 2G licences on a first-come, first-served basis in 2008 instead of auctioning them, costing the government up to $37bn (£23bn) in lost revenue.
He has denied any wrongdoing and says he is a victim of trial by media.