Story highlights 1979 case was one of New York's "oldest and most painful unsolved crimes," DA says

Hernandez had confessed to the kidnapping, but his attorneys say he is mentally ill

New York (CNN) A New York jury, with the conviction Tuesday of a bodega clerk in the 1979 kidnapping and killing of 6-year-old Etan Patz, brought to a close what a prosecutor called one of the city's "oldest and most painful unsolved crimes."

The guilty verdict against Pedro Hernandez, 56, in connection with a murder that sparked an era of heightened awareness of crimes against children , marks the end of an agonizing wait of nearly 40 years for Etan's parents.

"The Patz family has waited a long time, but we've finally have found some measure of justice for our wonderful little boy Etan," his father, Stanley, said.

Etan disappeared on May 25, 1979, as he walked to a school bus stop. In the early 1980s, his photo appeared on milk cartons across the country, the first time the method was used to help locate missing children.

Hernandez, who was convicted after the jury deliberated nine days, faces a maximum sentence of 25 years to life in prison at sentencing later this month.

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