Levi Aron, who has confessed to smothering and chopping up 8-year-old Brooklyn boy Leiby Kletzky, has been called a sick individual by Mayor Michael Bloomberg, even as his lawyer said he suffers from some hallucinations and hears voices.

Leiby Kletzky, the 8-year-old missing Brooklyn boy, was found brutally killed and dismembered on Wednesday morning. His chopped-up remains were found in the murderer's refrigerator and a nearby dumper. The murderer has already pleaded guilty of killing.

Kletzky disappeared on Monday, when he was on the way to his parents' home from a summer camp. This is the first time Kletzky was coming home alone with his parents' agreement.

After Kletzky went missing, police launched a massive search for him. Soon they found a Brooklyn resident Levi Aron and found that he might be involved with this case through a surveillance video tape. At that time, Aron was paying a dental clinic. Kletzky asked him for the direction because the boy was walking alone for the first time and got lost.

Even the video tape didn't show what happened next but investigators are sure that Kletzky finally got into Aron's 1990 Honda Accord.

When the police arrived at Aron's apartment and asked about the whereabouts of the boy, a shirtless Aron pointed out towards the kitchen. The police found the blood on the refrigerator's door and three bloody knives next to a cutting board. In the refrigerator, the boy's feet were found. The other remains were found in a red suitcase tossed into a nearby dumper.

It is every parent's worst nightmare, Police Commissioner Raymond Kelly.

He has indicated to me that he hears voices and has had some hallucinations, attorney Pierre Bazile said.

Aron told the investigators that he had panicked and had killed the boy, when he found the police were searching for Kletzky.

Levi Aron, 35, is a stock clerk at the Empire State Supply Co. hardware store on McDonald Avenue in Kensington. His co-worker told a local Brooklyn news outlet that even though Aron is strange, he was normal on Tuesday. I can't believe this, he said. He was a strange guy, but he was here yesterday and he was fine after killing this little boy.

Aron lives alone in an apartment, but his parents live in the same building. And there's no indication that Aron knew the Kletzky family, even they live less than a mile way.

Aron, who has already confessed to the murder, was arrested and has been accused of second-degree murder. However, the medical examiner's office said they are still investigating how the boy was killed.

On Wednesday evening, about 8,000 people mourners gathered to Kletzky's funeral around a Borough Park synagogue. People spoke and chanted in Yiddish and Hebrew. There's no greater pain than this, a mourner said.

Mayor Bloomberg also expressed his condolences to the boy's family: Some things are just inexplicable, a nine-year-old boy with a whole future, his life ahead of him and then gone. Obviously the perpetrator is a very sick individual, and this is the sort of thing — I don't know what's going to happen with the investigation, but it's hard to see how something like this could've been prevented.

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