WASHINGTON  Thousands of pages of internal e-mail and once-secret Congressional testimony showed Tuesday that Karl Rove and other senior aides in the Bush White House played an earlier and more active role than was previously known in the 2006 firings of a number of United States attorneys.

Aides to former President George W. Bush have asserted that the Justice Department took the lead in the dismissals, which set off a political firestorm that lasted months. Mr. Rove played down his role in the firings in a recent interview and in closed testimony last month before Congressional investigators.

But the documents, released by the House Judiciary Committee after a protracted fight over access to White House records and testimony, offer a detailed portrait of a nearly two-year effort, from early 2005 to 2007, by senior White House officials, including Mr. Rove, to dismiss some prosecutors for what appear to be political reasons.

Internal e-mail messages in the spring of 2005 at the White House showed that there was widespread unhappiness with David Iglesias, the United States attorney in New Mexico, because of the perception among top Republicans that he was dragging his feet on voter fraud and corruption investigations involving Democrats.