NEW YORK (CBSNewYork/AP) — Sparks flew Tuesday at the trial of the man accused of killing Etan Patz when a prosecutor cross-examined the defense’s star witness.

Former federal prosecutor Stuart GraBois had spent years trying to connect convicted pedophile Jose Ramos to the 1979 disappearance of 6-year-old Etan.

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Ramos had told GraBois he was 90 percent sure that a boy he picked up near Washington Square Park was Etan.

At one point, GraBois had jailhouse informants inserted into the cell with Ramos.

Prosecutor Joan Illuzzi-Orbon seized on that, asking GraBois if he instructed them to get a confession, WCBS 880’s Irene Cornell reported.

“No,” GraBois answered. “I said, ‘See what you can find out.'”

Illuzzi-Orbon pressed on. “Isn’t it possible that you convinced Ramos he took the Patz boy?” she asked.

“No,” GraBois said. “The mantra was ‘leave no stone unturned.'”

Illuzzi-Orbon suggested GraBois was so obsessed with the case that he followed up on psychic tips.

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There was a particularly condensending tone of ridicule in her voice as she repeated “psychic tips, psychic tips!”

Finally, GraBois responded by saying he has been a lawyer for 48 years and prosecutor for 10 and “your tone should be modified.”

“And you should start answering questions and stop shouting at me,” Illuzzi-Orbon fired back.

The defense hopes to plant reasonable doubt in jurors’ minds about the guilt of Pedro Hernandez, who is on trial.

Hernandez confessed to police in 2012 that he offered Etan a soda to entice him into the basement of the SoHo bodega where he worked. Then, Hernandez said, he choked the boy and dumped him in a box with some curbside trash. Etan’s body has never been found.

Defense lawyers say Hernandez’s confession is fiction, dreamed up by a mentally ill man with a low IQ and a history of hallucinations and fueled by more than six hours of police questioning before Hernandez was read his rights.

While he has denied killing Etan, a civil court found Ramos liable for the boy’s death in 2004 after he stopped cooperating with questioning.

Etan’s disappearance ushered in a new protectiveness into American parenting. He became one of the first missing children featured on milk cartons. His parents advocated for legislation that created a nationwide law-enforcement framework to address such cases.

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