Two former longtime employees at Bernard Madoff's firm were arrested on Thursday in connection with the investigation into the now-imprisoned swindler's Ponzi scheme, the FBI said.

The former employees, Jo Ann Crupi and Annette Bongiorno, had worked for Madoff for 25 and 40 years, respectively.

Federal prosecutors earlier this year had filed civil complaints against the two women, seeking the return of at least $7 million. The complaints said Crupi and Bongiorno had bought luxury cars and invested in property with funds obtained from defrauded Madoff investors.

Crupi was arrested at her home in Westfield, New Jersey, and Bongiorno was arrested in Florida, an FBI spokesman said.

Charges against the defendants are expected to be unsealed later Thursday in Manhattan federal court, the spokesman said.

Lawyers for Crupi and Bongiorno could not immediately be reached for comment. The U.S. attorney's office in New York did not immediately return a call.

Madoff, 72, is serving a 150-year sentence at a North Carolina federal prison after admitting last year to running what prosecutors called a $65 billion Ponzi scheme.