Nearly four decades after six-year-old Etan Patz disappeared on his way to school never to be seen again, a former store clerk has been found guilty of murdering the child in a New York City basement after enticing him there with a soft drink.

The jury convicted 56-year-old Pedro Hernandez after nine days of deliberation. While the verdict elicited tears from some in the courtroom audience, Hernandez did not visibly react.

“The Patz family has waited a long time, but we’ve finally found some measure of justice for our wonderful little boy, Etan,” Stanly Patz, Etan’s father, said.

Pedro Hernandez was convicted of killing Etan Patz in 1979 (Reuters)

“I’m really grateful that this jury finally came back with which I have known for a long time - that this man, Pedro Hernandez, is guilty of doing something really terrible so many years ago.”

“I am truly relieved, and I’ll tell you, it’s about time. It's about time,” he added, according to the Associated Press.

Pedro Hernandez abducted the boy four decades ago

Hernandez’s lawyers said that they planned to appeal the verdict and said their client was a mentally ill man who struggled to tell the difference between what was real and what was not. They said that his confession was the result of that struggle between fact and fiction.

The May 1979 disappearance of Etan as he walked to his bus stop by himself for the first time became one of the highest profile crimes in New York’s history, and led to parental anxiety nationwide about leaving children unattended.

Etan’s image was one of the first to be affixed to a milk carton when the search for him and his abductor spread across the country. Etan’s body has never been found and he was declared formally dead in 2001 after years of investigation yielded few results.

Prosecutors re-opened the case seven years ago and in 2012 Hernandez was arrested. A video-taped confession showed Hernandez telling investigators that he had kidnapped Etan and took him into the basement of the shop where he worked to strangle him.