WASHINGTON - A lengthy investigation by the US Senate has debunked charges by a Republican congressman that military analysts identified Mohamed Atta and other Sept. 11 hijackers before the attacks, according to a committee aide familiar with the report.

In a letter to members of the Senate Intelligence Committee, Sens. Pat Roberts and John D. Rockefeller dismissed suggestions by Rep. Curt Weldon, R-Pa., that defense analysts ignored analysis that could have prevented the attacks. Roberts, R-Kan., is outgoing chairman and Rockefeller, of West Virginia, is the senior Democrat who will assume the chairmanship next month.

They concluded "there was no evidence Mohamed Atta or any hijackers were identified prior to 9/11," said the committee aide, who spoke on condition of anonymity because the aide was not authorized to speak publicly on the subject.

An internal Pentagon assessment already had dismissed Weldon's charges as unfounded. But the letter from Roberts and Rockefeller is the first rejection from Capitol Hill. The letter was obtained and first reported Tuesday by the Los Angeles Times.

Weldon, a 10-term Republican who lost his seat in the Nov. 7 election, repeatedly contended a secret military unit called "Able Danger" searched large amounts of data to link four Sept. 11 hijackers to al-Qaida more than a year before the attacks.

In September, the Pentagon's inspector general found some employees recalled seeing an intelligence chart identifying Atta as a terrorist before the attacks. But the report said those accounts "varied significantly" and witnesses were inconsistent at times in their statements.

At the time, Weldon questioned the "motives and the content" of the report and rejected its conclusions, which he said relied on cherry-picked testimony. Weldon could not be reached Tuesday for comment.

According to the committee aide, Roberts and Rockefeller found similar problems in their investigation.

Weldon lost his seat to Democrat Joe Sestak, a retired Navy admiral who called for troops to be withdrawn by the end of 2007.

Just weeks before the election, the FBI raided the homes of Weldon's daughter and a close friend in an investigation of whether the congressman improperly helped the pair win lobbying and consulting contracts.