Congress had set up the panel in 1998. Extending its life paves the way for public release of more documents, some of which have been classified for nearly 60 years.

The working group has released about 8 million pages of documents, panelists said. The documents have shown links between the government and Nazis who would have been charged with war crimes if they had not agreed to work with U.S. intelligence agencies.

"We want to know what our government knew about the people who were Nazis … when they put them to work for our government," said Amanda Flaig, a spokeswoman for Sen. Mike DeWine (R-Ohio), who co-wrote the legislation. "It's important to know so that we don't repeat the past."

A CIA official said the agency had turned over 1.5 million documents to the civilian panel and had stepped up its efforts to provide other relevant materials.

"There are no new war-criminal relationships" to reveal between the CIA and Nazis, the official said.

Most remaining documents deal with relations between the agency and members of German SS military units who committed no war crimes, the official said.

The CIA recently provided those materials to the panel under pressure from Congress because the SS itself "was judged at Nuremberg as a criminal organization," the official said.

"Now the agency is being more forward-leaning. If someone was in the SS but had not committed war crimes, the material dealing with that individual would be reviewed and likely released," the official said.

The CIA acknowledged to the panel in a February letter obtained by the Los Angeles Times: "The documents concerning acts performed by Nazi war criminals, to include members of the SS, on behalf of the CIA are relevant and are subject to declassification review."

Members of the working group were pleased to get more time to review the CIA documents.

"This body of material will shed light on whether the United States government's willingness to employ former Nazis was in fact counterproductive," said Richard Ben-Veniste, a Washington lawyer and panel member.

"Because many of these individuals proved highly unreliable and were routinely subject to blackmail by Soviet counterintelligence, there is a practical as well as moral lesson to be learned from the history of this period."

The founder of the Simon Wiesenthal Center, a Jewish human rights group, praised the action to extend the life of the panel.

"That it's a national security issue 60 year later is not plausible," Rabbi Marvin Hier said.

"Without this committee, the intelligence agencies would be able to have a blanket claim of national security and under the Freedom of Information Act. It would be very difficult to get important documents."

Times staff writer Greg Miller contributed to this report.