Richard Esposito and Rhonda Schwartz contributed to this report.
Despite a flat denial from the Department of Justice, federal law enforcement sources tonight said ABC News accurately reported that Speaker of the House Dennis Hastert is "in the mix" in the FBI investigation of corruption in Congress.
Speaker Hastert said tonight the story was "absolutely untrue" and has demanded ABC News retract its story.
Law enforcement sources told ABC News that convicted lobbyist Jack Abramoff has provided information to the FBI about Hastert and a number of other members of Congress that have broadened the scope of the investigation. Sources would not divulge details of the Abramoffâ€™s information.
"You guys wrote the story very carefully but they are not reading it very carefully," a senior official said.
One focus involves a letter Hastert wrote in 2003 urging the Secretary of the Interior to block an Indian casino that would have competed with tribes represented by Abramoff.
The letter was written within days of a fund-raiser held for Hastert at Abramoffâ€™s restaurant in Washington. Federal campaign records show more than $26,000 was raised at the time from Abramoff and his clients.
Hastert has denied doing anything unlawful and says he has a long history of opposing certain types of Indian casinos.
ABCâ€™s law enforcement sources said the Justice Department denial was meant only to deny that Hastert was a formal "target" or "subject" of the investigation.
"Whether they like it or not, members of Congress, including Hastert, are under investigation," one federal official said tonight.
The investigation of Hastertâ€™s relationship with Abramoff is in the early stages, according to these officials, and could eventually conclude that Abramoffâ€™s information was unfounded.
Officials said the next logical investigative step would be for the FBI to seek a wide range of documents from the members of Congress named by Abramoff, including letters and business documents.
A spokesman for Hastert said the office had received no subpoenas or requests for documents.