NSA investigates terrorists, US citizens and ... Congress?

[MegaRock]

WASHINGTON (CNN) -- The FBI wants to interview top members of Congress from both parties about the leak to The New York Times concerning the National Security Agency's domestic surveillance program, sources told CNN.

The Capitol Hill newspaper Roll Call first reported that the FBI wanted to question federal legislators as part of its probe. The sources do not know if any members have been interviewed yet.

The FBI declined to comment.

The New York Times in December reported the existence of the surveillance program, which allows phone calls between the United States and overseas to be monitored without a court warrant so long as one party is a terror suspect. It was authorized by President Bush shortly after the September 11, 2001, attacks.

Only a few members of the House and Senate were briefed on the NSA program before it became public.

One source with knowledge of the investigation said: "There is only a certain universe of people who had this information and could have leaked it. Obviously any investigation would focus on that universe. If members who had knowledge were not interviewed, then any investigation would not be complete."

A spokesman for the House Intelligence Committee would not say whether its chairman, Rep. Peter Hoekstra, had been asked for an interview, but did say the Michigan Republican has been questioned on other investigations. "It's his belief that you must vigorously pursue all illegal leaks to send a message that there is no tolerance," spokesman Jamal Ware told CNN.

A House Intelligence Committee official said discussions are going on between congressional officials and the Justice Department and FBI about the interviews.

"The full scope of this is still being negotiated between all sides," the official said. "There are a broad range of issues to consider. There are constitutional separation of power issues that have to be resolved."

A spokesman for Rep. Jane Harman, D-California, ranking minority member on the House Intelligence Committee, said she has not been contacted about "any inquiry" regarding the NSA leak.

House Minority Leader Nancy Pelosi, D-California, who used to sit on the Intelligence Committee, said, "It is not unusual ... that the investigation would include all of those who had access or had been briefed about the program. If asked, I will certainly participate in that inquiry."

Pelosi's spokeswoman, Jennifer Crider, said Pelosi has not been notified that the FBI wants to interview her about the leak.

A source with knowledge of the leak investigation said separation of powers should not be an issue regarding interviews with members of Congress, saying that lawmakers have been interviewed in previous leak inquiries.

When the FBI was contacted for reaction, agency spokesman Richard Kolko said, "This is a sensitive and ongoing matter, and it would be inappropriate for the FBI to comment on this investigation at this time."