MINNEAPOLIS (AP) -- A central Minnesota man confessed Tuesday to abducting and killing 11-year-old Jacob Wetterling nearly 27 years ago, putting to rest a mystery that had haunted the state and led to changes in national sex offender laws.

Danny Heinrich made the admission as he pleaded guilty to federal child pornography charges that could put him behind bars for decades.

Asked whether he abducted, sexually assaulted and murdered Jacob, Heinrich said: "Yes I did."

Heinrich, 53, of Annandale, led authorities to Jacob's buried remains in a central Minnesota field last week, according to a law enforcement official who spoke to the AP on condition of anonymity because of the ongoing case. The Stearns County Sheriff's Office said Jacob's remains were identified Saturday.

Appearing in court, he admitted abducting Jacob from a road near the boy's home in the central Minnesota community of St. Joseph on Oct. 22, 1989. Authorities named him as a person of interest in Jacob's disappearance last October when they announced the child pornography charges.

Heinrich had long been under investigators' scrutiny. They first questioned him shortly after Jacob's abduction, but he maintained his innocence and they never had enough evidence to charge him. They turned a renewed spotlight on him as part of a fresh look into Jacob's abduction around its 25th anniversary.

As part of that effort, investigators took another look at the sexual assault of 12-year-old Jared Scheierl, of Cold Spring, nine months before Jacob's disappearance. Investigators had long suspected the two cases were connected.

Using technology that wasn't available in 1989, investigators found Heinrich's DNA on Scheierl's sweatshirt, and used that evidence to get a search warrant for Heinrich's home, where they found a large collection of child pornography. The statute of limitations had expired for charging him in the assault on Scheierl, but a grand jury indicted him on 25 child pornography counts.

The AP typically doesn't identify victims of sexual assault, but Scheierl has spoken publicly for years about his case, saying it helped him cope with the trauma and that he hoped it could help investigators find his attacker and Jacob's kidnapper.

Jacob's abduction shattered childhood innocence for many rural Minnesotans, changing the way parents let their kids roam. His smiling face was burned into Minnesota's psyche, appearing on countless posters and billboards over the years.

His mother, Patty Wetterling, always kept hope her son would be found alive. She became a national advocate for missing children, and with her husband, Jerry Wetterling, founded the Jacob Wetterling Resource Center, which works to help communities and families prevent child exploitation. In 1994, Congress passed a law named after Jacob that requires states to establish sex offender registries.

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