Investigators found two handwritten manifestos espousing white supremacy in the car and jail cell of a white man accused of killing nine black parishioners at a Charleston, South Carolina, church last year, according to a court document filed on Monday.
Investigators also found handwritten letters and a list of churches among the papers belonging to accused killer Dylann Roof, who faces trial on 33 federal crimes including hate crimes, obstruction of religious practice and firearms charges.
Roof has offered to plead guilty if prosecutors agree to drop the death penalty, his defense attorney has said. But prosecutors have so far refused to make a plea deal over the June 2015 slaying of nine Bible study members at the historic Emanuel African Methodist Episcopal Church.
The shootings shook the country and intensified debate over U.S. race relations, already roiled at the time by high-profile police killings of unarmed black people.
Much of the evidence against Roof has been sealed but the latest details were disclosed in a court filing by prosecutors listing the expert witnesses they plan to call at the trial, which is scheduled to begin on Nov. 7.