After four days of forensic of searching and digging in a SoHo basement, the search for evidence in the Etan Patz investigation appears to be winding down. No human remains have been found, but investigators tell NBC New York they did collect some hair samples, a piece of paper, and part of a wall with a mysterious stain on it. That so-called "stain of interest" was sent to an FBI lab in Quanitico, VA to determine if it's blood. An official tells the Wall Street Journal a second stain on a piece of concrete was discovered, but is not believed to be human blood.

The tents that were set up for investigators on Prince Street have been broken down, but an FBI investigator told the Post that the dig was stopped yesterday for "operational reasons," likely related to the heavy rain. Officials say the Prince Street operation will likely conclude today. The hair samples recovered have not been identified yet, and the significance of the scrap of paper is unknown, but one investigator tells NBC New York it was important enough to be collected.

Today the Times has an interesting look at how the investigation was reinvigorated by an FBI agent who took over the cold case after his predecessor got promoted. Relatively junior agent Thomas MacDonald spent years reanalyzing the case from scratch, interviewing witnesses again, and closely investigating other suspects besides the primary one, Jose Ramos, a junk collector currently imprisoned for child molestation. Ramos briefly dated a woman who walked neighborhood children home during a bus strike—Etan was one of the children she escorted.

But MacDonald took a special interest in local handyman Othniel Miller, who had a workshop at 127 Prince Street's basement. Miller, now 75 and a stroke victim, has been cooperating with authorities, who interviewed him after his ex-wife said he had sexually assaulted a young niece. The Times reports:

Agents have repeatedly interviewed Mr. Miller, who is 75 and has had several strokes. They also tracked down his ex-wife, Phyllis, who a second person familiar with the case said told agents that her former husband had raped a 10-year old girl. “Given that recent information, he skyrocketed to the top of the list,” the first law enforcement official said about how agents came to focus on Mr. Miller.

During one interview, agents watched Mr. Miller as he grew aroused while he looked through a book of images of children, two law enforcement officials said. At another point during questioning, when agents asked Mr. Miller about the possibility of Etan’s being buried in the basement, he asked back, “What if the body was moved?”

The day before Etan went missing 33 years ago, he came home from school with a dollar Miller had given him for helping with a carpentry project. Investigators interviewed Miller in the days following Etan's disappearance, and while they noticed freshly-poured concrete in the basement, they did not dig it up.

Miller's lawyer issued a statement yesterday saying, "Mr. Miller decries these efforts to sully his good reputation and destroy his family. He has absolutely no responsibility for the terrible tragedy that befell young Etan Patz, and he grieves for Etan’s fate, as all New Yorkers have for decades."