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FBI, NYPD resume search for Etan Patz, who went missing in 1979

The 6-year-old disappeared in 1979, but the FBI says they are optimistic that they can 'bring closure' to the investigation. NBC's Ron Allen reports.

Updated at 5 p.m. EDT: NEW YORK -- Police and the FBI were back Thursday at a lower Manhattan building where Etan Patz went missing in 1979, NBCNewYork.com reported.

Patz was six years old when he disappeared May 25, 1979 on his way to the school bus stop, touching off one of the most high-profile missing child cases in New York history. He was among the first missing children ever shown on the side of a milk carton, and President Ronald Reagan declared May 25 National Missing Child Day in his honor.

Officials are searching the basement of a building on Prince Street in SoHo, based on a re-examination of evidence, police said. Authorities plan to dig up the basement, which is connected to a handyman who had contact with Patz just before he disappeared, according to a law enforcement official.

The 15-by-30 basement is at 127B Prince Street, about 200 feet from the building where Patz lived.

Authorities in the afternoon got an alert from a cadaver dog they brought in.

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NYPD spokesman Paul Browne said there is dry wall in the basement that wasn't there in 1979, and authorities plan to remove it and dig through the basement and brick walls.

Sources also say they have evidence to suggest Patz had been in the basement before.

Investigators recently went to the DA seeking a search warrant  based on the new information. They plan to be at the building through the week and possibly into the weekend, officials told NBCNewYork.com.

NYPD detective William Butler profiles his search for Etan Patz.

Authorities from the city medical examiner's office were also on scene to help determine whether any findings are human remains.

FBI spokesman Tim Flannelly said the Patz family was notified before the search began.

"We're hoping that there will be real results," Flannelly said. "This little boy disappeared in 1979, and here we are in 2012 still hopeful that we can bring closure to the investigation."

Two years ago, Manhattan District Attorney Cyrus Vance Jr. said he was reopening the case, taking a fresh look at the evidence.

Vance declined to specify at the time why the case was reopened.

Patz was legally declared dead in 2001.

Stanley K. Patz via AP

This undated image provided Friday, May 28, 2010 by Stanley K. Patz shows Patz's son Etan, who vanished in New York on May 25, 1979.

The prime suspect has long been Jose Ramos, who had connections to Patz's former babysitter. Ramos is serving 20 years in prison in Pennsylvania for an unrelated child molestation case.

In the 1980s, U.S. Attorney Stuart GraBois resumed the investigation of Ramos. When GraBois asked Ramos how many times he had sex with Patz, Ramos "broke down," GraBois told CBS' "60 Minutes" in 2000.

During that questioning, Ramos admitted to having taken a young boy to his apartment on May 25, 1979, and that he later recognized the boy as Patz, declared missing on the news.

But Ramos said the boy had refused his advances, and that he let him go. Without any evidence, GraBois was not able to charge Ramos with the crime.

The Patz family filed a civil case against Ramos, and in 2004 State Supreme Court Justice Barbara R. Kapnick declared Ramos responsible for Patz's death. The family was awarded $2 million, which they have not collected.

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