WASHINGTON - Federal prosecutors have subpoenaed another of U.S. Rep. Chaka Fattah's aides, seeking testimony from his district office manager, Dolores Ridley.

Ridley, in a Jan. 16 message to House Speaker John Boehner, said she had been subpoenaed by the U.S. District Court for the Eastern District of Pennsylvania "for grand jury testimony in a criminal case."

Lawmakers and their staffers are required to notify the speaker when they receive a subpoena.

Two of Fattah's longtime political aides have already pleaded guilty for their role in a scheme in which prosecutors say Fattah, a Philadelphia Democrat, used them to steer federal grants through a series of nonprofits in order to repay an illegal campaign loan.

Fattah was not directly named in either plea deal and has said that he has never "been involved in illegal conduct."

He has accused prosecutors of misconduct in an investigation that has stretched on for years without any formal accusation against him.

Prosecutors last year subpoenaed documents from Fattah's office, and in a recent court hearing sought access to seven years of e-mails from his private e-mail account. One of his top aides on the House Appropriations Committee was also subpoenaed last year.

A Fattah spokeswoman wrote in an e-mail that his office "has no additional details" on the latest subpoena beyond what was included in Ridley's letter to Boehner.

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