A former director at investment bank Goldman Sachs has been taken into custody on charges relating to a hedge fund insider trading case.
Rajat Gupta, 62, is accused of providing illegal information to hedge fund manager Raj Rajaratnam.
Rajaratnam was sentenced to 11 years in jail for insider trading earlier this month.
Mr Gupta’s lawyer denied his client, who also headed consulting giant McKinsey, had done anything wrong.
Civil fraud charges were brought against Mr Gupta by the US Securities and Exchange Commissioner in March.