WASHINGTON (AP) – Donald H. Rumsfeld, the former Secretary of Defense, and other top former Pentagon brass denied any cover-up and rejected personal responsibility Wednesday for the military’s bungled response to Army Ranger Pat Tillman’s friendly-fire death in Afghanistan.

“I know that I would not engage in a cover-up. I know that no one in the White House suggested such a thing to me. I know that the gentlemen sitting next to me are men of enormous integrity and would not participate in something like that,” Mr. Rumsfeld told a House committee.

It was Mr. Rumsfeld’s first public appearance on Capitol Hill since President Bush replaced him with Robert Gates late last year. He reiterated previous testimony to investigators that he didn’t have early knowledge that Tillman was cut down on April 22, 2004, by fellow Rangers, not by enemy militia, as was initially claimed.

The truth was kept from the public and Tillman’s own family until five weeks later – May 29, 2004. Tillman’s mother, Mary Tillman, his brother, Kevin, and other family members watched silently from the back row at Wednesday’s hearing before the House Oversight and Government Reform Committee.

Afterward they left without commenting.

General Richard Myers, who retired as chairman of the Joint Chiefs of Staff, said he learned of the likelihood of friendly fire toward the end of April but that it wasn’t his responsibility to inform the White House or the Tillman family.

“I don’t think there’s any regulation that would require me to do anything,” said General Myers. He blamed the Army.

“This is the responsibility of the United States Army, not of the office of the chairman, so I regret that the Army did not do their duty here and follow their own policy,” General Myers said.

Mr. Rumsfeld and General Myers both said they couldn’t remember precisely how or when they learned of Tillman’s death or that it might be friendly fire. Mr. Rumsfeld said he didn’t recall discussing the Tillman issue with the White House until the fratricide became public.

At the White House, presidential spokesman Tony Snow said the administration stands by Mr. Rumsfeld’s comment that there was no cover-up of how Tillman died.

“I’m certainly not going to contradict Secretary Rumsfeld,” Mr. Snow said.

“It is deeply regrettable that this sort of thing happened, and you try to make sure that it doesn’t happen at anytime,” he added.

Tillman’s death received worldwide attention because he had walked away from a huge contract with the National Football League’s Arizona Cardinals to enlist in the Army after 9/11.

Committee Chairman Henry Waxman, Democrat of California, aired his frustration at the repeated denials of responsibility from the four witnesses: Mr. Rumsfeld, General Myers, retired General John P. Abizaid, the former commander of the U.S. Central Command, and retired General Bryan Douglas Brown, former commander of the U.S. Special Operations Command.

“You’ve all admitted that the system failed. The public should have known, the family should have known earlier, whoever was responsible,” Mr. Waxman said as the hearing ended. “None of you feel you personally were responsible but the system itself didn’t work.”

” ‘The system didn’t work, errors were made’ – that’s too passive. Somebody should be responsible, and we’re trying to figure that out,” Mr. Waxman said.

Greeting Mr. Rumsfeld as he entered the hearing room were two activists who held signs reading “war criminal.”

“Are you not ashamed?” one said. Mr. Rumsfeld didn’t react. The activists renewed their chants after the hearing ended, shouting “Donald Rumsfeld, you’re a war criminal.” Again, Mr. Rumsfeld didn’t acknowledge them.

Mr. Rumsfeld was mostly sober and measured in his testimony. On occasion there were flashes of the cocky, combative Mr. Rumsfeld known to the public from Pentagon briefings.

Representative Dennis Kucinich, Democrat of Ohio, demanded to know whether there was a White House and Defense Department strategy to manage press portrayals of the war and other events.

“Well, if there was, it wasn’t very good,” Mr. Rumsfeld remarked.

“Well, you know, maybe it was very good,” Mr. Kucinich objected loudly. “Because you actually covered up the Tillman case for a while, you covered up the Jessica Lynch case, you covered up Abu Ghraib, so something was working for you.

“Was there a strategy to do it, Mr. Rumsfeld?”

“Congressman, the implication that ‘you covered up’ – that’s just false, you have nothing to base that on, you have not a scrap of evidence or a piece of paper or a witness that would attest to that,” Mr. Rumsfeld replied hotly. “I have not been involved in any cover-up whatsoever.”

The congressional inquiry comes a day after the Army laid most of the blame for the response to Tillman’s death on Philip Kensinger, a retired three-star general who led Army special operations forces after the Sept. 11, 2001, attacks.

The Army censured Kensinger for “a failure of leadership” and accused him of lying to investigators probing the aftermath of Tillman’s death. A review panel made up of four-star generals will decide whether Kensinger should have his rank reduced.

Army Secretary Pete Geren insisted, however, that there was no intentional Pentagon cover-up. The committee issued a subpoena Monday for General Kensingers’ testimony but U.S. marshals weren’t able to deliver it.

General Kensinger’s attorney, Charles W. Gittins, told The Associated Press Tuesday night that General Kensinger was on business travel and had declined to “participate in a hearing that is all about show and no substance.”