According to the authorities, the raids took place at the offices of Loch Capital Management, Level Global Investors and Diamondback Capital Management.
The latter two funds were both run by former employees at SAC Capital although no one currently working for the latter was accused of any wrong doing.
An unnamed source familiar with the matter stated that further raids are expected to take place over the course of the next few days.
Richard Kolko, an FBI spokesman, said: âThe FBI is executing court-authorized search warrants in an ongoing investigation.â
The raids are thought to be part of a three-year probe into insider trading that could see a large number of financial consultants, investment advisors and analysts arrested by the authorities.
Preet Bharara, US Attorney in Manhattan, is thought to be spear heading the investigation and working alongside the federal authorities as well as the Securities and Exchange Commission (SEC).
Meanwhile, the FBI announced, in an unrelated case, that it has charged a former financial advisor with defrauding investors of more than $2 million.
By Jim Ottewill