As a grand jury is reviewing the murder case against Levi Aron, police and Brooklyn officials say stores' surveillance video made a crucial difference in solving the murder of eight-year-old Leiby Kletzky. NY1's Vivian Lee filed the following report.

Levi Aron, 35, remained in protective custody under suicide watch Friday, as he awaited psychiatric evaluation and a grand jury reviewed evidence for his felony murder charges. Defense lawyers said the man accused of killing and dismembering eight-year-old Leiby Kletzky hears voices, and they want to find out more about his mental state before trial.

On Monday afternoon, prosecutors say Aron was approached by Leiby, who was wandering lost after leaving a day camp in Borough Park, Brooklyn.

By early Wednesday, police had discovered some of Leiby's dismembered body parts in Aron's refrigerator and other body parts in a dumpster in Sunset Park.

The crucial element that identified Aron a suspect in the boy's disappearance and death was surveillance video, and Brooklyn resident Yaakov German was the first man to find that footage.

German's son taught Leiby at the day camp, and as soon as they heard that the boy was missing, the father and son tried to track the boy's movements through the neighborhood.

Leiby walked along 44th Street and was supposed to turn onto 13th Avenue to meet his mother.

German found the first sign that Leiby missed that turn in video from the Variety Corner convenience store on 14th Avenue, a block farther on.

"I searched [the video] at 5:03 [p.m. Monday], when kids were coming, to 5:15. In those 15 minutes, I saw the image [of of the boy] with the knapsack, with the two-toned shirt. That was Leiby," German said.

"Now the camera was a really good lead, to see what happened," said store owner Bernat Rosenberg.

German hit more than 30 homes and businesses along 44th Street, asking to see their surveillance tapes. Some refused, but at a limo service company three blocks farther on, he found video showing a boy dressed like Leiby get into a man's car.

"We see somebody open the door, the kid goes in, closing the door, a gold car. We see the other camera showing him going to the front of the car, getting into his seat and his car going out," German said.

The images German found included video of the man from the car entering a dental office before driving off with the boy. Detectives went to that office and found Aron's address, which Police Commissioner Ray Kelly said pegged Aron as the prime suspect.

One of the Hasidic community's clergy liaisons with the New York City Police Department said German deserves a lot of credit for tracking down the video and handing over that information about the dentists's office.

For German, the hardest part is knowing Leiby's family is in such pain, after he offered a glimmer of hope.

"While I found the first video clip, I called the father direct. I had his number. He said, 'Yaakie, thank you so much. If you find anything else, keep on calling us.' Like it brought joy for one minute," German said.

Brooklyn Assemblyman Dov Hikind, who also helped lead the search for the boy, wants to encourage the use of surveillance cameras with a new bill.

The so-called "Leiby Initiative," which will also be introduced by Brooklyn Assemblyman Peter Abbate and State Senator Diane Savino, would offer an annual $500 real estate tax credit to city store owners who purchase, install and maintain surveillance cameras.

Meanwhile, crime scene investigators continued to search Aron's Kensington home for evidence on Friday. They also checked to see if Aron had any improper contact with children in the past.

Aron is due back in court later this month.