HOLLYWOOD, Fla. - A serial killer who died years ago is the person who decapitated the 6-year-old son of

America's Most Wanted

host John Walsh in 1981, Florida police said yesterday.

The announcement closed a case that has vexed the Walsh family for decades, launched the television show about the nation's most notorious criminals, and spurred changes in how police look for missing children.

At an emotional news conference with John and Reve Walsh and their three children, Hollywood Police Chief Chadwick Wagner said there was no new evidence in the case that began July 27, 1981.

Still, after what he called a meticulous review and talks with investigators, he said he had concluded that a pedophile and serial killer, Ottis Toole, abducted and killed the 6-year-old 27 years ago.

If Toole, who died in prison 12 years ago, were still alive, he would be arrested and probably convicted of Adam's murder, Wagner said.

"Who could take a 6-year-old and murder and decapitate him? Who?" John Walsh said at the news conference.

Toole had twice confessed to the killing but later recanted. He claimed responsibility for hundreds of murders, but police determined most of the confessions were lies.

Toole's niece told John Walsh that her uncle had confessed on his deathbed in prison that he killed Adam.

The Walshes had long derided the probe as botched, and John Walsh had said he believed Toole killed his son. Still, yesterday he praised the Hollywood police for closing the case.

Adam Walsh went missing from a Hollywood mall on July 27, 1981. Fishermen discovered his severed head in a canal 120 miles away two weeks later. The rest of his body was never found.

Authorities made a series of crucial errors, losing the bloodstained carpeting in Toole's car - preventing DNA testing - and the car itself. It was a week after the boy's disappearance before the FBI got involved.

For all that went wrong, the case contributed to huge advances in police searches for missing youngsters.