BIRMINGHAM, Ala. — The church where four black girls died in a racist bombing in 1963 was designated as a national landmark Monday, with Attorney General Alberto Gonzales recalling their memory amid a string of recent attacks against churches in Alabama.

Speaking at the pulpit of Birmingham's Sixteenth Street Baptist Church, Gonzales likened the deadly bombing of the old building to a series of arsons that hit 10 rural Baptist churches since Feb. 3.

Investigators have said they don't know a motive in the arsons, but there is no racial pattern. Five of the churches had white congregations and five black. All were Baptist, the dominant faith in the region, and mostly in isolated country settings.

But Gonzales said the fires are a reminder "there is still work to be done" in ensuring equal justice and fighting discrimination.

Gonzales called the Sixteenth Street Baptist Church "a catalyst for the cause of justice" as he referred to the children killed when a Ku Klux Klan bomb went off there on Sept. 15, 1963.

"We protect this place for them," Gonzales said.

At the ceremony, Interior Secretary Gale A. Norton signed a proclamation adding the church to a list of about 2,500 places that carry the title of National Historic Landmark.

Church members gave Gonzales a lengthy ovation, and the pastor, the Rev. Arthur Price Jr., called the historic landmark designation "major for us." Price said a previous attempt to have the 200-member church designated a federal landmark failed, although he was unsure of details.

The audience included relatives of the four girls who were killed — Addie Mae Collins, Carole Robertson and Cynthia Wesley, all 14, and Denise McNair, 11.

Sixteenth Street Baptist Church was an important meeting place for activists during the civil rights era, and the bombing became a worldwide symbol illustrating the depth of racial hatred in the South at the time. Three Klansman were convicted in the blast, the last in 2002.

The bomb knocked out part of a wall and heavily damaged the bathroom where the girls died.