Etan Patz: Officials Discuss How the Case Was Reopened In ABC News Exclusive The FBI said that work was progressing "slowly and methodically."

April 21, 2012 -- When Cy Vance was running for Manhattan District Attorney, he and his opponents were approached by Stan Patz, the father of missing child Etan Patz, and asked to re-open the case, help the family get closure and bring to justice the person who kidnapped and murdered the 6-year-old boy in 1979.

Vance made a commitment to Patz: if he was elected he would re-examine the case. He did so shortly after he was elected, meeting multiple times with Patz and former federal prosecutor Stu Grabois, who had devoted much of his career to the Patz case.

In January 2010 the case took on new life. Dormant since the former Manhattan DA, Robert Morgenthau, opted not to present evidence against one suspect to a grand jury, it got a fresh look by a team of prosecutors and an FBI agent assigned to it. Old interviews were reconsidered, old evidence re-examined, and a fresh round of interviews with subjects of the original investigation began.

The probers soon returned to the brick and concrete basement at 127B Prince Street, a few doors down from where Etan Patz disappeared May 25 1979, a space that appeared to never have been searched. It was also where the lives of the prime suspect of Grabois's investigation, Jose Ramos, and Othniel Miller, a carpenter and handyman who used the basement as a workshop, intersected.

Ramos was already in prison, serving 20 years for raping two boys in Pennsylvania. Miller had never been really subjected to a significant investigation. Miller's basement workshop floor was re-concreted around the time of Patz disappearance, but it was never thoroughly searched let alone dug up. One reason, investigators recall, was that the boy's mom, Julie Patz, described Miller, now 75, as "a family friend."

The Patz's have not returned calls by ABC News to discuss the reinvigorated investigation and have posted a notice at their home asking the media to respect their privacy . And Ramos, it seems, had a key to Miller's workshop, frequented it, and appears to have performed some odd jobs for Miller, sources say. Miller, who has been charged with no crime in connection with the Patz case, is alleged by multiple sources to have seen Patz the night before he disappeared and to have given the boy a dollar.

The 1979 disappearance sparked a massive citywide search, but now the FBI and New York City police have brought the case right back to the block where Patz stepped out of his family's home at 113 Prince Street in his fluorescent sneakers and airline pilot's cap to head the two blocks to his school bus stop alone for the first time.

Federal agents and New York City police began Thursday to tear up the concrete floor of the basement at 127 Prince St. By Saturday much of the digging had been done, and chunks of concrete large and small had been lifted up and out.

Prosecutors began focusing on the Prince Street basement room following a positive hit by NYPD and FBI cadaver dogs.

Special odor-absorbing pads were placed in the room, capturing the scent of human remains -- even decades old -- that police cadaver dogs were able to detect. The pads were sent down to the dogs in Virginia, and when a dog there got a positive hit, a dog was brought into the basement, sources said.

Investigators then twice interviewed Miller before obtaining a warrant and beginning the dig.

NYPD Commissioner Ray Kelly on Friday said an array of new technology unavailable to law enforcement in 1979 including x-rays and black lights are being used in the investigation.

The new probe is reexamining the decades-old assumption that Patz was abducted by convicted pedophile Jose Ramos. It has not ruled Ramos out, and Miller is not named as a suspect. Miller's lawyer, Michael Farkas, says his client is innocent and cooperating with authorities.

Some of the strongest evidence against Ramos, who has an extensive criminal history of molesting boys, came in what became known as "the 90 percent confession." It took place in the Southern District of New York office of Grabois, when he was investigating the case. Grabois and a detective listened as Ramos told them that the boy in the Etan Patz missing persons fliers resembled the boy he had taken home for sex the day before the disappearance.

"I'm 90 percent sure," he told Grabois, that the boy was the one he "took to my home for sex." He described several of his actions with Etan, but then asked for an attorney and later changed his story.

Farkas would not comment on whether sex crime allegations brought against Miller by an ex-wife several years after the Patz disappearance were part of the information presented to a judge by the Manhattan District Attorney's office in order to obtain a search warrant. The District Attorney's office has declined any comment on the case accept to acknowledge it reopened it in January 2010 and that the warrant was requested by that office.

On Saturday, the FBI said that work was progressing "slowly and methodically." Federal Agent Tim Flannelly, of the FBI New York field office said that no revelations were likely to be forthcoming over the weekend.