WASHINGTON (AP) _ President Clinton, declaring Sunday a ``national day of mourning,'' said today he and first lady Hillary Rodham Clinton will fly to Oklahoma City to attend memorial services for victims of the explosion.

``All of America will be there in spirit and are there today,'' Clinton told reporters at the White House.

Clinton said he was briefed late Thursday by Attorney General Janet Reno on the status of the investigation into the bombing that claimed dozens of lives. ``I am well satisfied by the progress that is being made,'' he said.

However, he urged Americans not to ``rush to any conclusion unsupported by known evidence and that we give the investigators the space they need to do their job.''

``They are working hard. They are moving ahead,'' he said.

The Clintons will participate in the 3 p.m. CDT Sunday observances at the state fairgrounds, said White House spokeswoman Ginny Terzano.

Clinton may also meet with family members and tour the site of the bombed-out building, but White House officials said details of his schedule have not yet been decided.

``Hillary and I have decided to go to Oklahoma City on Sunday to be a part of the memorial service and to be with the families of the victims and the people of Oklahoma City,'' Clinton said.

Clinton said he wanted ``to ask people in their places of worship and in their homes all across America to pray for the people there and for the community.''

He spoke on the South Lawn of the White House as he prepared to board his helicopter for a flight to Harve de Grace, Md., where he was to give a speech commemorating the 25th anniversary of Earth Day. Aides said he might also mention the Oklahoma City bombing in that speech.

Clinton will also devote his Saturday radio address to the tragedy, and broadcast it from the East Room before an audience that will include children.

In his remarks today, Clinton said he remains ``very concerned with how the children in Oklahoma City and indeed the children throughout America must be reacting to a horror of this magnitude.''

``And my message to the children is that this was an evil thing. And the people who did it were terribly, horribly wrong. We will catch them and we will punish them.''

``But the children of America need to know that almost all the adults in this country are good people who love their children and love other children,'' he added. ``And we're going to get through this,'' he added.

The visit adds a day to what had been a three-day swing through the Midwest.