The CIA has intelligence agents inside Osama bin Laden's al Qaeda network -- as it did before the Sept. 11, 2001, attacks -- but they are not within the terrorist leader's inner circle where key information about any future attack would be discussed, a senior intelligence official said yesterday.

"They are beyond foot soldiers but not in the inner circle," the official said. The agents -- Afghans, Pakistanis, Uzbeks and others recruited and run by CIA case officers -- "are more senior than the agents [the U.S. had] three years ago who were on the periphery," the official said.

Aided by these agents, electronic intercepts, satellite imagery, and extensive help from foreign intelligence services, the United States over the past two years has captured or killed two-thirds of bin Laden's top aides and broken up plots against U.S. embassies, U.S. and foreign aircraft, and ships and other targets worldwide.

Although the U.S. intelligence community believes that al Qaeda today is far less capable than the team that put together the Sept. 11 attacks, bin Laden "looks to the United States still as the brass ring," another senior intelligence official said. "They still want to continue to attack us in the ways they did three years ago," he said during a Wednesday briefing, which was held on the condition that reporters not disclose his name or the identity of two other senior intelligence officials who spoke.

This is the first time that CIA officials have publicly described with such specificity the placing of agents and other steps aimed at cracking al Qaeda -- the sort of information that the agency generally guards very closely.

They made the revelations as part of a response to the stern criticism of the agency this week by the Sept. 11 commission. It portrayed U.S. intelligence as having failed dramatically before the 2001 attacks, largely because it lacked significant sources of human intelligence about bin Laden's organization.

The comments came at the briefing, held the day before the commission report was released, and in interviews yesterday that elaborated on some points.

"We have busted plots repeatedly" that were undertaken by "serious al Qaeda players" involving both aircraft and ships -- some in Northeast and Southeast Asia -- one official at the briefing said.

He said intelligence on the possibility of other attacks has recently been strong. "I wouldn't characterize what we have now as chatter," he said. "I think we have some fairly specific information that al Qaeda wants to come after us."

In 2001, the officials said, U.S. technical intelligence did intercept conversations of the Sept. 11 plotters over an al Qaeda command-and-control phone link. But U.S. analysts could not understand their "doubletalk" enough to disrupt the operation, the first official said.

"They [al Qaeda members] became aware that we were sitting on those phones, and they became doubly cautious and their doubletalk doubled as they progressed, so we were thwarted," he said. CIA Director George J. Tenet was able to give warnings of terrorist activity in the summer of 2001 because "we were able to pick up this drumbeat of threat . . . with rumors from the camps . . . [and] information from technical collection," he said.

A former senior intelligence official yesterday recalled listening to Air Force Lt. Gen. Michael V. Hayden, director of the National Security Agency, which intercepts communications, "20 or 30 times during the summer saying he believed the attack would come tomorrow."

The three senior intelligence officials at Wednesday's briefing said they recognize some of the failures pointed out by the commission, but feel that new approaches already in place are addressing the problems.

The Sept. 11 commission has called for a far-reaching revamping of the U.S. intelligence system by creating a national counterterrorism center within the president's office.

It would coordinate and oversee efforts by the CIA and other intelligence agencies, the U.S. military and domestic law enforcement officials. The center would report to a new national intelligence director who would have budgetary and operational control over the CIA and the other 14 intelligence offices in the government.

Acting CIA Director John E. McLaughlin has said the agency will study the recommendations, but he is on record as opposing the idea of a new intelligence director within the government.

The CIA's skepticism about the proposed structural changes was reflected in this comment by one of the officials conducting the briefing: "We have to be careful . . . to really understand where the intelligence community is today and to not do something that rolls back advances we've made."

Osama bin Laden "looks to the United States still as the brass ring," a senior intelligence official said.