Police in India have arrested a man in connection with the alleged buying of votes during a 2008 vote of confidence in parliament over a civilian nuclear deal with the US.
Sanjeev Saxena, alleged to be an aide of a politician, was held on Sunday.
India's Congress-led government survived the vote amid claims of vote buying.
If the government had lost the vote, India would have faced early elections, casting the nuclear deal in doubt.
Mr Saxena's arrest came days after India's Supreme Court criticised the police in the capital, Delhi, for carrying out a "shoddy probe" into what is called the "cash-for-votes" scandal.
In July 2008 two days of debate on the nuclear accord in parliament ended in uproar with allegations of vote buying.
Opposition Bharatiya Janata Party (BJP) members waved wads of currency notes in the air, alleging that they had been offered bribes to abstain.
India's media was awash with reports of alleged defections and desertions among MPs ahead of the vote.
The opposition claimed that a news channel had secretly recorded the alleged bribe taking.
The channel handed over the tapes to parliament speaker Somnath Chatterjee for investigation.