NEW YORK (CBSNewYork) — One of the first detectives to question Pedro Hernandez in the 1979 killing of 6-year-old Etan Patz testified Monday about the interview that led to a murder confession.

Detective James Lamendola told jurors he coaxed Hernandez into his confession by talking to him about the cycle of abuse, WCBS 880’s Irene Cornell reported.

Hernandez, who is on trial for murder, told officers of being beaten with a horse whip as a child by his drunken father in Puerto Rico. The detective repsonded by saying that people who have been abused as children often grow up to abuse children themselves.

That was the breaking part for Hernandez.

His previously calm demeanor changed, the detective said. Hernandez started crying, clutching his stomach, lying down in a fetal position. He complained of being cold. The detective brought him a jacket, and the questioning continued.

Lamendola said he assured Hernandez he wasn’t trying to trick him. As he put it: “The lies have to stop. The truth needs to be told.”

Finally, Hernandez, now 53, told him, “OK, I did it. I did Etan Patz. I choked him, and I’m going to prison for the rest of my life.”

Hernandez confessed on videotape 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, still alive, in a box with some curbside trash.

The child’s body was never found, but he was legally declared dead as the investigation spanned decades.

Defense attorneys maintain that Hernandez is bipolar and schizophrenic and that his confessions are false.

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.