New York, Jan 7 - Federal prosecutors have doubled the amount they believe Sri Lankan billionaire Raj Rajaratnam skimmed off an insider New York trading scheme, charging his profits were a whopping $36 million.

The allegation was contained in court papers filed Tuesday in Manhattan opposing Rajaratnam's bid for reduced bail, Bloomberg financial news service reported. Investigators were worried that the founder of Galleon Group hedge fund could flee along with the ill-gotten money into his homeland, media reports said Wednesday.

Investigators had originally estimated that Rajaratnam had only pocketed about $17 million in the scheme, which involved payments to company insiders for secret information about developments inside publicly-traded companies.

The practice violates US rules of transparency governing all publicly-traded corporations.

Sri Lankan authorities are also investigating whether Rajaratnam financed prominent front organizations for Tamil rebels in that country.

Rajaratnam, who is also being sued by the US Securities and Exchange Commission, was arrested in October and charged with earning millions of dollars from stock trades made with inside information from corporate officials and hedge fund executives.

In all, six of the 21 people charged in two overlapping insider-US-trading schemes have pleaded guilty. The schemes have touched IBM, the international leading chip manufacturer AMD, and the internet giant Google, forcing some top managers in those companies to resign.

The 52-year-old investment wizard founded one of the world's largest hedge funds, Galleon, with branches in London, Singapore, Mumbai and Menlo Park, California. He is free on $100 million bail. He was identified in 2009 by Forbes as the 559th richest person in the world, with a net worth of $1.3 dollars.

Investigators used wiretaps - normally reserved for organized crime and drug casese - for the first time ever in probing insider trading. US prosecuting attorney Preet Bharara has likened the white-collar crime to mafia practices and said it spread far beyond the 21 arrests.

Among those mentioned in the charges are Rajiv Goel of Intel Capital, Anil Kumar of McKinsey & Co and Robert Moffat of IBM IBM Corp. Two former officials at Bear Stearns Asset Management, Danielle Chiesi and Mark Kurland, who were affiliated with Galleon's

New Castle Partners, were also arrested.

In Tuesday's filing, prosecutors said they will expand the charges to include allegedly wrongfully-shared information on the acquisition of ATI Technologies Inc by Advanced Micro Devices (AMD) Inc. That deal allegedly gave Rajaratnam illegal tips from a paid-off insider. Galleon bought ATI securities before the AMD announcement, reaping $19 million in illegal profits, according to prosecutors.

"The government now has evidence that Rajaratnams illicit gains yielded profits that were at least twice as large as those previously alleged," assistant US attorneys Joshua Klein and Jonathan Streeter wrote in the court filing.

Rajaratnam and Chiesi, an executive at New Castle Funds LLC, were indicted by a federal grand jury in December.

Shortly after his arrest, Rajaratnam announced plans to liquidate his hedge funds. (dpa)