House and Senate leaders plan to formally honor the victims of a critical turning point in the civil rights movement next month just days before the 50th anniversary of the attack.

President Obama signs a bill Friday in the Oval Office commemorating the lives of the four girls killed in the 1963 Birmingham church bombing. (Jacquelyn Martin/AP)

Congressional leaders will host a ceremony on Sept. 10 at the Capitol's National Statuary Hall to bestow the Congressional Gold Medal on the "four little girls" killed in the 16th Street Baptist Church bombing in Birmingham, Ala., on Sept. 15, 1963.

The girls -- Addie Mae Collins, 14; Denise McNair, 11; Carole Robertson, 14; and Cynthia Wesley, 14 -- died inside their Sunday school classrooms when dynamite, set to explode by a timer, blew up the African American church just 18 days after the March on Washington. Propelled in part by public outrage over the bombing, Congress passed the Civil Rights Act the next year.

The House and Senate voted earlier this year to posthumously grant one of the nation's highest civilian honors to the girl. On Friday, President Obama called it "a great privilege" as he signed the legislation in a private Oval Office event attended by the girls' living relatives,

Language in the legislation specifically recognizes how the children's deaths marked a turning point in the years-long fight for equal rights for the nation's African American citizens.

The Congressional Gold Medal is awarded annually by Congress. Golfing pro Arnold Palmer and global economist Mohammed Yunus are the most recent recipients, while other civil rights leaders have received the award, including Martin Luther King Jr. and his wife, Coretta Scott King, Rosa Parks, the “Little Rock Nine,” baseball great Jackie Robinson and the Tuskegee Airmen.

Despite the critical role their tragedy played in the advancement of civil rights, the slain girls have received few posthumous honors. There’s a college scholarship program named for them, and the city of Birmingham has planned an outdoor memorial to the girls that officials say is near completion.

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