As they returned to the Capitol Monday, federal lawmakers were taking a break from writing the country's laws to salute the two police officers shot to death in the national landmark. "I apologize to the nation," said the grief-stricken father of the man charged with the rampage.

House members and senators planned to take up a resolution honoring Capitol Police officers Jacob Chestnut, 58, and John Gibson, 42, shot to death Friday by a man who ran through a metal detector and started firing a handgun.As the flags over the Capitol remained at half-staff, congressional staff and employees returned to the Hill for the first time since the shootings. "We're beginning to move back in, and attempting to create an ongoing, ordinary office atmosphere," House Oversight Committee Chairman Bill Thomas, R-Calif., said on NBC's "Today."

Still, security was heightened, with additional police officers stationed on the Capitol grounds, at entrances to the building and throughout its corridors. The area where the killings occurred was off-limits to the public, a yellow rope draped across the entrance that the gunman used.

The suspect in the shootings, Russell E. Weston Jr., 41, of Rimini, Mont., remained in serious condition at D.C. General Hospital with bullet wounds to the chest, arms, thigh and buttocks.

His parents, Russell Weston Sr. and Arbah Jo Weston, said Monday they hadn't spoken to their son since the shooting. "It just doesn't make any sense. We didn't even know he was going to be leaving," his father said on ABC's "Good Morning America."

"I feel so bad about it," he said on NBC, speaking from his home in Valmeyer, Ill. "I feel so bad for the people that he killed. I apologize to the nation."

Weston, who authorities said has a history of mental illness, was to have a hearing in absentia Monday in U.S. District Court on charges of killing a federal law enforcement officer. The case was being transferred from a District of Columbia court where papers had been filed Saturday charging him in the deaths of the two 18-year veterans of the Capitol force.

On Tuesday, the coffins of Chestnut and Gibson will lie in the Capitol Rotunda, an honor usually afforded only to presidents and national heroes, including Abraham Lincoln, John F. Kennedy and Douglas MacArthur.

The Rotunda will be closed to the public for 30 minutes for a memorial service involving the officers' families, Capitol Police colleagues and the members of Congress they gave their lives protecting. President Clinton and Vice President Al Gore also are to attend the service.

"To our congressional family: Like all of these things, it takes an incident for people to really tell you how much they really love you," Capitol Police Chief Gary Abrecht said Sunday. "We always thought we had a pretty good relationship with the congressional community and now we know we are loved very greatly."

Gibson will be buried Thursday after a funeral in suburban Lake Ridge, Va. A day later, Chestnut, a 20-year Air Force veteran, will be buried in Arlington National Cemetery.

A Capitol visitor, Angela Dickerson, 24, of Chantilly, Va., suffered wounds to the face and arm from stray gunshots and was discharged from a hospital following an overnight stay.

Clinton spoke by telephone Sunday to Chestnut's widow, but was not able to make contact with Gibson's widow, said officials traveling with the president in New Mexico. They said he also spoke with Dickerson.

The shootings did not scare tourists away from the Capitol, which remained open all weekend to visitors as usual. A large pile of flowers sat on the building's steps in memory of the two slain officers.

The deaths of Chestnut and Gibson have given new impetus to efforts to improve security on the Capitol grounds, which have been open to the public even as access to other federal buildings grew tighter in recent years.

One plan given new impetus is for construction of a visitors' center, possibly underground, to serve as a way station for tourists as well as provide for greater security because visitors would be screened for weapons before they entered the Capitol building.