India's former telecoms minister, Andimuthu Raja, has been charged with conspiracy, forgery and fraud in connection with a multi-billion dollar corruption scandal.The allegations relate to the sale in 2008 of mobile phone licences for a fraction of their real value.
Auditors estimate this could have cost the country nearly $40bn (£24.5bn) in lost revenue.
Mr Raja denies wrongdoing. Last year he was forced to resign over the issue.
Investigators say Mr Raja deliberately favoured some companies over others when allocating valuable second generation (2G) mobile phone licences.
He is accused of issuing the 2G licences on a "first-come, first-served" basis instead of auctioning them.
India has the world's fastest growing mobile market, with about half a billion subscribers.
The BBC's Mark Dummett in Delhi says the scandal has become a major political crisis for Prime Minister Manmohan Singh's government, eroding its reputation at home and abroad.
The country has seen a series of high-profile corruption investigations in recent months.