FBI and NYPD investigators have discovered a "stain of interest" on a concrete wall while taking apart a SoHo building basement in their search for the remains of Etan Patz, according to law enforcement sources.
The discovery was made Saturday in the ongoing search for clues in the case of the 6-year-old boy who went missing 33 years ago on his short walk to the school bus stop.
NBC New York was first to report the break in the cold case on Thursday.
By Saturday, investigators had finished ripping up the basement's concrete floor with jackhammers and saws, and were digging through the dirt in hopes of finding the boy's remains, or any other evidence.
It was while investigators were taking apart the basement floor and walls that they found a "stain of interest" on a concrete wall, according to law enforcement sources. Officers from the NYPD Emergency Services Unit used a chainsaw to cut out a piece of the wall, which is being preserved for analysis at an FBI laboratory in Virginia.
While using an illuminating light, forensics experts found the spot on the concrete wall.
According to a source, the spot could be blood.
The significance of the stain is still unknown, but it is believed to have been there for some time.
Other debris was also being tested, a process that could last into next week, chief police spokesman Paul Browne said.
The search was halted Sunday afternoon due to heavy rain, FBI spokesman Jim Margolin said. They will resume digging Monday.
At the time of Patz's disappearance, the 13-by-62 basement at 127B Prince Street was being used as a workshop by Othniel Miller, a handyman who was friendly with the Patz family.
Miller, now 75, has been interviewed by investigators several times over the years, but he recently made statements that raised their suspicions, according to law enforcement sources.
In a recent interview with investigators, he blurted out “What if the body was moved?” according to an official.
Sources also say they have evidence to suggest Patz had been in the basement before.
Miller hasn't been named a suspect, and his lawyer says he has nothing to do with the case.
Investigators Saturday were mostly concentrating their search towards the rear of the basement, where a cadaver-sniffing dog recently picked up a scent.
It's unclear what the renewed probe may turn up, if anything.
"We're hopeful that we can bring some level of comfort to the parents, perhaps find some — obviously, the body of this poor child — but evidence that may lead to a successful investigation in this case," Police Commissioner Ray Kelly said. He was a lieutenant working on organized crime cases when Patz vanished.
As for whether authorities were optimistic, he said, "I really can't say."
Investigators have also questioned a second person, Jesse Snell, in connection with the re-examination of evidence. NBC New York has learned that on the morning Patz disappeared in 1979, Snell was observed at the building where police are searching now, and also worked with Miller. Investigators would not elaborate on why they met with Snell.
One other man has remained a longtime possible suspect: Jose Ramos, a drifter and onetime boyfriend of Patz's baby sitter. In the early 1980s, he was arrested on theft charges, and had photos of other young, blond boys in his backpack. But there was no hard evidence linking Ramos to the crime.
He is in prison in Pennsylvania on a separate case.
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