The FBI and NYPD are searching the basement of a building in SoHo for the remains of 6-year-old Etan Patz, who went missing 33 years ago, NBC New York first reported Thursday.

Patz disappeared after leaving his home just down the block, on his way to the school bus stop on May 25, 1979.

Officials are searching the basement of a building on Prince Street that is connected to a handyman who had contact with Patz just before he disappeared, according to a law enforcement official.

Authorities recently got an alert from a cadaver dog they brought into the 13-by-62 basement at 127B Prince Street, about 200 feet from the building where Patz lived. (See map below)

Law enforcement sources say investigators have talked to the handyman, Othneil Miller, and that he made statements that raised their suspicions.

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

Investigators have also questioned a second person of interest in connection with the case, according to sources.

Miller did not answer his door on Thursday at his Brooklyn apartment.

NYPD spokesman Paul Browne said there is dry wall in the basement that wasn't there in 1979, and authorities are removing it and digging through the basement and brick walls.

Investigators recently went to the DA seeking a search warrant  based on the new information. They plan to be at the building into the weekend, officials told NBC New York.

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."

The search for Patz in 1979 was one of the most high-profile missing child cases in New York City history. President Ronald Reagan declared May 25 National Missing Child Day in his honor.

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

The DA declined to specify at the time why the case was reopened.

Patz was legally declared dead in 2001.

Neighborhood Reacts to New Search for Patz

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 another 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 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 Etan's murder. The family was awarded $2 million, which they have not collected.

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