HOLLYWOOD, Fla. -- South Florida law enforcement officials announced Tuesday they had finally solved the 1981 killing of a little boy whose father went on to be an advocate for missing children and later gained fame as the host of "America's Most Wanted."

Six-year-old Adam Walsh was shopping with his mother at the Hollywood Mall in the summer of 1981 when she lost sight of him after he went to play video games. Despite a frantic search, the boy was never seen alive again.

His kidnapping case would become murder case two weeks later when his remains were found.

Hollywood police have announced that a Jacksonville man named Ottis Toole, long considered the lead suspect in Adam Walsh's murder, has finally been conclusively linked to the crime.

"Who could take a 6-year-old and murder and decapitate him? Who?" an emotional John Walsh said at Tuesday's news conference. "We needed to know. We needed to know. And today we know. The not knowing has been a torture, but that journey's over."

Investigators' agreement on who killed Adam's came too late for any prosecution: Toole died in prison more than a decade ago.

Toole had confessed to the killing, but later recanted.

Toole claimed hundreds of murders -- the first when he was 14 years old -- but police determined most of the confessions were lies. Toole's niece told the boy's father, John Walsh, her uncle gave a deathbed confession to the crime.

Toole, who was born in Jacksonville in 1947, died in 1996 while serving a death sentence for a conviction in the 1984 arson-murder of 64-year-old George Sonnenburg.

In 1982, Toole locked Sonnenburg in a home in Jacksonville and set the house alight, killing him.

He was subsequently convicted of killing a prostitute whose identity was never established and a 19-year-old Tallahassee girl.

In the past, John Walsh and his wife, Reve, were critical of the detectives handling the case for misplacing key evidence and overlooking important leads, Lohse reported.

The Walshes always believed Toole was the killer, although there was never enough evidence to charge him.

Hollywood Police Chief Chadwick Wagner, who launched a fresh review of the case after taking over the department last year, acknowledged numerous missteps in the investigation and apologized to the Walshes.

"I have no doubt," John Walsh said. "I've never had any doubt."

The killing had a huge impact on public policy. It sparked the creation of Code Adam, an internationallyrecognized missing child program, and the Adam Walsh Child Protection and Safety Act, which was signed into law in July 2008.