Pedro Hernandez has been arrested in the 1979 murder of Etan Patz, New York Police Commissioner Ray Kelly announced Thursday evening.

Kelly said it is unlikely that any remains of the 6-year-boy will ever be found.

A tipster's report led to the arrest, he said. 

Hernandez, 51, of Maple Shade, N.J., will be booked on a charge of second-degree murder in the slaying of the boy, who vanished on his way to school in SoHo, Kelly said. 

Hernandez, who had worked at a convenience store near Etan's home, confessed after hours of police questioning, Kelly said. Kelly said Hernandez told police he lured the boy to the store with the promise of a soda, then took him into the basement and choked him.

He was remorseful, and I think the detectives thought that it was a feeling of relief on his part, Kelly said. We believe that this is the individual responsible for the crime.

It's not immediately clear whether Hernandez, arrested in New Jersey Wednesday, has a lawyer, CBS reported.

Kelly said Hernandez confessed to the crime. Hernandez worked at a convenience store near Etan's Lower Manhattan home. A law enforcement official says Hernandez told investigators this week he suffocated the boy and left his body in a box in an alley.

Sources say that Hernandez admitted to luring the boy into the store with candy, strangling him, and placing the body in a box. He said he put the box out with the trash and when he came back later, it was gone.

He basically said he did it, a law enforcement source told CBS News. Investigators say while Hernandez's story may be difficult to corroborate, they believe he is credible.

It is unclear whether investigators have been able to corroborate the Hernandez' account, The New York Times reported. Without any trace of human remains or other forensic evidence, any prosecution could face significant evidentiary hurdles.