Dylann Roof has been found competent to stand trial in the killing of nine black worshippers at a South Carolina church.

U.S. District Judge Richard Gergel announced the decision Friday, CBS News justice reporter Paula Reid reports.

Jury selection has been scheduled to start on Monday.

Roof’s lawyers questioned his competency earlier this month on the eve of jury selection. They have carefully ensured their reasons for wondering about his mental state have not become public, and Gergel has issued several redacted motions and rulings.

Six women an three men were killed in the shooting the night of June 17, 2015 at historic Emanuel AME Church in Charleston, South Carolina. Credit: CBS

Gergel closed the two-day hearing that began Monday amid concern its contents could taint potential jurors’ views of Roof.

Prosecutors filed court papers saying Roof appears competent to them because he has shown proper behavior toward court personnel and been attentive at other hearings.

Gergel sealed his reasons for finding Roof competent, saying that information could keep him from having a fair trial.

The 22-year-old white man is charged in federal court with hate crime, obstruction of religion and other counts for the deadly June 2015 attack at Emanuel African Methodist Episcopal Church in Charleston.