A former bodega stock clerk arrested for allegedly luring 6-year-old Etan Patz off a SoHo street and strangling him in a basement has been placed on suicide watch at a hospital as a precaution, NBC 4 New York has learned.

Pedro Hernandez, 51, was arraigned from Bellevue Hospital via video feed on a single charge of 2nd-degree murder. The charge comes 33 years to the day that Patz disappeared off a SoHo street in a tragic case that mystified New York City for decades.

According to the criminal complaint, Hernandez told police he strangled Patz and placed him inside a plastic bag, causing his death. His court-appointed lawyer, Harvey Fishbein, told the court that Hernandez is a schizophrenic and had both auditory and visual hallucinations. Fishbein requested a hearing to determine his client's mental fitness.

Hernandez is in isolation and receiving a medical evaluation at the hospital. Another source told NBC 4 New York that this evaluation is precautionary and that such extra steps in a case like this are often routine.

Relatives have said Hernandez has a history of some mental issues.

Patz vanished on his way to a school bus in a case that drew international attention and changed the way parents felt about letting their young children go off alone.

Police said Hernandez had admitted to luring Patz into a bodega where he worked, near the boy's house, and choking him to death in the basement.    

Police Commissioner Ray Kelly said police focused on Hernandez, who now lives in Maple Shade, N.J., after the Missing Persons Squad received a tip from someone who remembered Hernandez speaking of having killed a child.

"In the years following Etan's disappearance, Hernandez had told a family member, and others, that he had 'done a bad thing' and killed a child in New York," Kelly said.

Based on that information, police went to question Hernandez.

Kelly said Hernandez, who worked at the bodega for about a month, confessed to police after he was picked up Wednesday night. Some of the interviews were conducted at the scene of the crime, Kelly said.

Kelly said the suspect had not given a reason for attacking Patz and said there was "no reason at this time" to suspect the boy was sexually abused. He said it was "unlikely" Patz's remains would ever be found and that Hernandez told them he put the boy's body in the trash.

Hernandez's lawyer on Friday asked reporters to be respectful of some of Hernandez's relatives assembled at the courthouse, including his wife, daughter and another man, who huddled together on a wooden bench, turning away interview requests for more than an hour.      

"It's a tough day. The family is upset. Please give them some space,'' Fishbein said.

His sister, Maria, who did not want her last name used, told NBC 4 New York on Thursday that her heart ached over the news of her brother's arrest and said she couldn't believe it. She said Hernandez had three children of his own and came from a family of 12 that emigrated from Puerto Rico in 1973.

Mayor Bloomberg said Thursday that the disappearance of Patz "broke the hearts of millions" across the nation, especially parents, and expressed sympathy again for the boy's family.

"I certainly hope that we are one step closer to bringing them some measure of relief," he said.

Manhattan District Attorney Cy Vance had pledged to reopen the decades-old cold case when he took office in 2010.

See a timeline of the case here.

The exhaustive search for Patz was renewed several weeks ago when police dug up the basement of a handyman's workshop near where Patz disappeared. A new layer of concrete had been laid over the foundation of the basement shortly after the boy vanished.

That search yielded no new evidence.

A lawyer for the handyman, Othniel Miller, said his client is "relieved by these developments, as he was not involved in any way with Etan Patz's disappearance."

One other man had remained a longtime possible suspect: Jose Ramos, a drifter and onetime boyfriend of Patz's baby sitter. But there was no hard evidence linking Ramos to the crime.

He is in prison in Pennsylvania on a separate case.

The boy's parents, Stan and Julie Patz, were reluctant to move or even change their phone number in case their son tried to reach out. They still live in the same apartment, down the street from the building that was examined in April. They have endured decades of false leads, and a lack of hard evidence.      

Police said the family had been notified of the arrest. See more about that here.

Stan Patz had his son declared legally dead in 2001 so he could sue Ramos, who has never been criminally charged with the boy's death and denies harming the boy. A civil judge in 2004 found Ramos to be responsible for the child's death.

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