Public hearings by a congressional panel looking into the Sept. 11 attacks probably will be delayed until September, about three months later than originally planned, congressional aides said Tuesday.

The delay comes as staff members from the House and Senate intelligence committees go through massive amounts of information related to the attacks to determine what information can be released.

The committees have been meeting jointly behind closed doors since June 4 to examine intelligence problems leading up to the Sept. 11 attacks and to recommend changes. Public hearings had been scheduled to begin June 25, but were delayed until after this week's July 4 recess.

No announcement was made on when they would resume, but two congressional aides, speaking on condition on anonymity, said they were unlikely to be held until September.

Rep. Porter Goss, chairman of the House Intelligence Committee, said he could not confirm or deny the September date, saying no announcement would be made until the committees' leaders meet next week.

Goss, R-Fla., said committee staff are trying to determine what information can be released to the public without compromising sources and methods used by intelligence agencies.

The committees are trying to get information "to the public in a way that's helpful to the public and not helpful to the terrorists," he said.

Goss said the committees must be flexible about the timing of public hearings.

"We've got a huge amount of information and we're trying to organize it in a meaningful and understandable way," he said.

It's not clear if delays in public hearings will affect the committees' plans to reach preliminary findings by fall and issue a final report by January.

Congress is looking to the inquiry to help determine whether major changes are needed at the FBI, CIA and other agencies.

President Bush's proposal for a Homeland Security Department seeks to address one of the biggest problems that became evident after the Sept. 11 attacks: the failure of agencies to share intelligence. The agencies would be required to feed intelligence to the department, which would analyze the information for possible threats.

Bush's proposal doesn't propose major changes in the agencies themselves, and Congress is unlikely to seek any until the new department is set up and the joint inquiry has issued findings.

However, some lawmakers say they will consider giving Homeland Security a stronger role than Bush proposed in dealing with intelligence agencies. This could include more access to raw intelligence and the ability to request specific information.