Nine more people have been arrested in the Galleon Group insider-trading scandal, bringing to 15 the number charged in the biggest hedge fund-related case in history.

The new arrests include Wall Street traders, lawyers and hedge fund managers, according to complaints filed in federal court in New York on Thursday,

The new charges come nearly three weeks after Raj Rajaratnam, the billionaire founder of hedge fund firm Galleon Group, and five others were arrested in the case. Rajaratnam is accused of masterminding the scheme.

Among those charged on Thursday were Zvi Goffer of Incremental Capital hedge fund; Arthur Cutillo, a former attorney with law firm Ropes & Gray; Jason Goldfarb, an attorney; Craig Drimal, a former employee in Galleon's office; and Emanuel Goffer, Michael Kimelman and David Plate, all associated with Incremental Capital.

The complaints allege that Zvi Goffer ran an insider trading network and paid sources for inside information. He provided his tipsters with prepaid cellphones so they could minimize the chances of getting caught when passing on tips, the complaint said.

Zvi Goffer worked at Schottenfeld, a New York-based broker dealer, for nearly all of 2007, the complaint said. He moved to Galleon in January 2008, where he worked for about eight months before quitting to start his own trading firm, Incremental Group.

Zvi Goffer's scheme involved shares of 3Com Corp and Avaya, according to the complaint.

Federal and state authorities planned to announce charges against 14 new defendants -- including those named on Thursday -- later in the day, sources familiar with the matter said. Authorities scheduled a news conference for midday.

Rajaratnam is accused of orchestrating an insider-trading network that brought in profits of more than $20 million. He is free on bail.

Among those entangled in the case are executives at several major companies, including International Business Machines Corp and Intel Corp.

Along with Rajaratnam, the others charged initially were Danielle Chiesi, a Rajaratnam associate and portfolio manager at hedge fund firm New Castle Partners; Mark Kurland, a co-founder of New Castle Partners; IBM's senior vice president, Robert Moffat; Intel Capital's Rajiv Goel; and Anil Kumar, an executive at management consulting firm McKinsey & Co.

Galleon, a prominent New York-based firm that once managed $7 billion and specialized in technology and healthcare companies, has shut down.

The scandal sent shockwaves through the financial world and unnerved the $1.4 trillion hedge fund industry at a time when performance was improving and investors were committing new money.

(Writing and reporting by Steve Eder; Reporting by Matthew Goldstein and Anupreeta Das in New York and Svea Herbst-Bayliss in Boston; editing by John Wallace)