In mournful tribute beneath the Capitol dome, President Clinton praised two slain police officers as heroes whose sacrifice "consecrated this house of freedom." Lawmakers and thousands of visitors joined Tuesday in a daylong outpouring of sympathy.

Jacob J. Chestnut and John Gibson, killed Friday by a Capitol intruder, "died in duty to the very freedom that all of us cherish," said House Speaker Newt Gingrich.The widows, children and other relatives of the slain men were seated for the memorial service, a few feet from the flag-draped coffins bearing the remains of their loved ones. All others in attendance stood.

Customarily, only presidents, members of Congress and military commanders are permitted to lie in the Rotunda. Congress made an exception in the case of the two fallen officers, and by early morning, hundreds of people were in line outside the Capitol waiting to pay their respects.

Some wept, some saluted, others simply stared at the caskets as the long line filed slowly up the Capitol steps and into the soaring Rotunda where the coffins rested. An honor guard, four Capitol Police officers in dress blue uniforms, stood somber watch.

Joining the mourners were delegations of law enforcement officials from across the nation.

Chestnut and Gibson were shot Friday afternoon when a gunman burst into the Capitol with a .38-caliber handgun. Chestnut was shot without warning, according to an account provided by officials, while Gibson and the gunman both fell following a furious exchange of gunfire at close range.

The suspect, Russell E. Weston Jr., 41, of Rimini, Mont., underwent surgery during the day for irrigation of his fractures. The hospital reported he was in stable condition.

Weston, who has a history of mental illness, has been charged with one count of killing federal officers, and faces a possible death penalty if convicted.

The memorial service was unprecedented - the nation's political leadership gathered in one of the most hallowed rooms in the land to mourn not a president or a general, but two men unknown outside their own communities.

Standing in a room graced with images of George Washington, Abraham Lincoln and other famous Americans, Senate Majority Leader Trent Lott said, "Today we honor two men that should rightly be recognized in this hall of heroes. It's appropriate today that we honor these two men who did their job, who stood the ground and defended freedom."

In his remarks at the brief ceremony, Clinton paid tribute to the "quiet courage and uncommon bravery" exhibited by Chestnut, Gibson and so many other police officers who are struck down in the line of duty.

Of the two men killed last Friday, he said, "In doing their duty they saved lives, they consecrated this house of freedom and they fulfilled our Lord's definition of a good life. They loved justice, they did mercy. Now and forever, they walk humbly with their God."

Chestnut, who was 58, and Gibson, 42, will be buried later this week at Arlington National Cemetery.