Indian MP Kanimozhi has been arrested in connection with the country's biggest corruption scandal.
She denies conspiracy and accepting bribes in the alleged mis-selling of telecoms licences, which auditors say cost the country about $40bn (£24.5bn).
A judge in the capital, Delhi, rejected her application for bail and she is due to be produced in court on Saturday.
Ms Kanimozhi, 43, is the daughter of M Karunanidhi, an important ally of the Congress-led federal government.
Her party colleague, former telecoms minister Andimuthu Raja, is already in jail in connection with the scandal.
He is accused of selling mobile telephony spectrum to firms at a fraction of their real value in exchange for bribes in 2008. He too denies all wrongdoing.
Along with Ms Kanimozhi, the court also rejected the bail application of a senior television executive.
"The bail applications are dismissed. Both the accused be taken into custody forthwith," news agency Press Trust of India quoted Judge OP Saini as saying.
Ms Kanimozhi's lawyer Ram Jethmalani said they would appeal in a higher court. Ms Kanimozhi has been charged under the Prevention of Corruption Act.
Prosecutors say she took a bribe of $47.6m (£29.3m) through Kalaignar TV - a channel run by the DMK party in the southern state of Tamil Nadu.
The issue of corruption has become a major talking point in India.
Mr Raja is on trial along with eight others, including two former civil servants. Several top company executives have also been arrested in connection with the so-called 2G case.
The telecoms scandal has badly damaged the reputation of the government, which has been hit by a series of corruption scandals.
India has the world's fastest growing mobile phone market, with about half a billion subscribers.