CHARLESTON, S.C. (Reuters) - The widow of the pastor who was among the nine people killed by white supremacist Dylann Roof told a federal jury on Wednesday she heard the gunman say he was not crazy during the rampage at a historic black church in South Carolina.

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Jennifer Pinckney said she hid with her 6-year-old daughter under a desk as Roof opened fire in an adjoining room at Emanuel African Methodist Episcopal Church in Charleston, where her husband, the Reverend Clementa Pinckney, and parishioners gathered for a Bible study meeting on June 17, 2015.

“I heard Mr. Roof say, ‘I’m not crazy. I have to do this,’” said Pinckney, the first witness to testify for U.S. prosecutors seeking the death penalty.

Prosecutors plan to call nearly 40 people to tell jurors how their lives were ripped apart by the shocking crime, carried out by Roof after churchgoers had their eyes closed in prayer.

Spouses and friends drew tears and laughter as they shared memories of victims Clementa Pinckney and Myra Thompson, who led Bible study the night of the shooting.

Roof also spoke to jurors, saying he was representing himself because he did not want them to hear any mental health evidence - but insisting he is not mentally ill.

The same jury last month found Roof guilty of 33 federal counts of hate crimes resulting in death, obstruction of religion and firearms charges.

“There’s nothing wrong with me psychologically,” said Roof, making no mention of the crime or the racist ideology prosecutors said spurred the massacre.

Roof, whose opening statement lasted mere minutes, also did not say whether he wants to live.

U.S. District Judge Richard Gergel ruled on Monday Roof was mentally fit to stand trial and act as his own lawyer, despite defense attorneys’ concerns about Roof’s plans to present no witnesses or evidence that might convince jurors to spare his life.

Assistant U.S. Attorney Nathan Williams told jurors Roof deserved to be executed, highlighting his months of planning, lack of remorse and his motivation.

“He killed them because of the color of their skin, because he thought they were less than people,” said Williams, who showed jurors photos of each victim.

Six weeks after Roof’s arrest, jailers found a handwritten note in his cell expressing white supremacist views, Williams said.

“I am not sorry,” Roof wrote. “I have not shed a tear for the innocent people I killed.”