The 6-year-old boy vanished in 1979, but so far, the fresh look at this cold case has turned up no remains.
The dig on Prince Street ended Monday, with the FBI releasing a statement saying, "The FBI has concluded the on-site portion of the search. The street and local businesses will be re-opened."
Chief police spokesman Paul Browne says the case remains a missing-person investigation, but authorities found no obvious human remains.
Officials hauled away large brown steel containers full of rubble and muddy dust from the blasted concrete floor and brought them to a landfill on Staten Island, where they will be preserved.
Though the search was over, some of the material gathered was still being examined.
The FBI lab in Quantico, Virginia will test a stain found on a concrete block that was chainsawed out of the basement wall.
The bureau's evidence response team reportedly tore up the floor, which had been laid down around the same time that Patz vanished.
Investigators then dug beyond that, going four to six feet deep into the soil.
An official with the city medical examiner's office had been on site during the search, and would have taken any potential human remains, including clothing or bones, but the official left without taking anything, one of the officials said.
Patz' parents were told Sunday that all the evidence collected will be analyzed.
They have not commented since the search began last week, and did not again Monday.
The case seemed to have been largely focused on Jose Ramos, a convicted child molester now serving time in Pennsylvania who had been dating Etan's baby sitter at the time the boy disappeared. In 2000, authorities dug up Ramos' former basement on the Lower East Side of Manhattan, but nothing turned up.
Stan Patz had his son declared legally dead in 2001 so he could sue Ramos, who has never been charged criminally and denies harming the boy. A civil judge in 2004 found him to be responsible for Etan's death.
But the focus shifted recently to Othniel Miller, who is now 75 and lives in Brooklyn. In 1979, Miller was a handyman who used the basement at 127B Prince St. as a workspace.
Miller, who was described by longtime residents as a neighborhood staple, was interviewed soon after the boy vanished. Investigators noticed at the time that the basement had a fresh concrete floor; his space was searched then but never dug up.
At the time, Miller gave investigators an alibi, though authorities are giving his account of the day a fresh look in part after recently interviewing his former wife, one of the officials said. Investigators spoke to Miller last week and decided to take a closer look at the basement, the official said.
Miller hasn't been named a suspect, and his lawyer Michael C. Farkas, says he "has absolutely no responsibility for the terrible tragedy." Farkas also decried efforts to "sully" his client's reputation.
"It's an ongoing investigation, and as I said from the beginning, these old cold cases shouldn't be forgotten," Manhattan District Attorney Cy Vance said.
At the site Monday, metal police barriers with white flowers woven through them were being taken down and the posh neighborhood full of galleries and boutiques was returning to normal. The basement will likely be re-filled with concrete, the bill handed over to officials for reimbursement.
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