Federal prosecutors in California are investigating a Goldman Sachs employee for insider trading, according to prosecutors and defense lawyers who attended a hearing in U.S. federal court in New York on Thursday.

The employee is suspected to have given inside information on two public companies to former Galleon Group co-founder Raj Rajaratnam, who was convicted last year in one of the largest insider trading cases in Wall Street history.

The investigation of the Goldman employee was divulged during a hearing involving the insider trading case against former Goldman board member Rajat Gupta.

A spokesman for Goldman Sachs declined to comment.

Gupta, a former director of Goldman Sachs Group Inc and Procter & Gamble Co

, was charged with illegally tipping his former friend Rajaratnam.

Gupta was indicted in October. He is the highest-ranking executive charged in a broad U.S. crackdown on insider trading at hedge funds and faces five counts of securities fraud and one count of conspiracy.

It does not appear the investigation in California is directly related to the Gupta case brought by federal prosecutors in New York. In fact, the federal prosecutor in New York handling the Gupta case did not notify his defense lawyer of the California investigation until last night.

The unidentified employee still works at Goldman, attorneys said. They did not provide any details about the investigation.

(Additional reporting by Lauran Tara LaCapra and Grant McCool; Editing by Matthew Goldstein and Dan Grebler)