Boise police remain mum about most details in the case of missing 8-year-old Robert Manwill, including whether they recovered any evidence from a search Friday night and Saturday morning at a home in the 6600 block of Southdale Avenue.

That search was aided by Boise State University officials using ground-penetrating radar, Boise police Deputy Chief Jim Kerns said.

"Our leads are narrowing and becoming more specific," Kerns said Saturday. "The Southdale residence became an area of interest due to a developing lead in the investigation - that location is one of many areas of interest."

Robert was reported missing to Boise police shortly after 10 p.m. Friday, July 24, from his mother's Vista Avenue-area apartment complex. Boise police officials say they have undisclosed evidence indicating that Robert may have been injured and may possibly be the "victim of a tragic event," but have not yet found him.

An area of the Hidden Hollow Landfill, near Northwest Boise, has been isolated by police tape in case authorities need to search trash dumped last weekend, but that area remained unstaffed Saturday morning.

Boise police Chief Mike Masterson said he is unaware of any list ranking suspects in the case, which has involved hundreds of interviews with family, neighbors and registered sex offenders. "We are not focused on any one specific area," Masterson said Saturday. "We are doing a thorough investigation."

A makeshift memorial for Robert - consisting of several stuffed animals, melted candles, a Bible, green ribbons, and a few pictures and notes expressing hope for the boy's safe return - sprung up Friday night on the sidewalk across from his mother's apartment. On Saturday afternoon, a few prayer candles were still lit.

For the second day in a row, the boy's mother, Melissa Jenkins, and her boyfriend, Daniel Ehrlick Jr., did not attend the daily police news conference.

Family spokeswoman Trisha Burrill, Robert's aunt, seemed to address Jenkins' absence when she told reporters Saturday that "every member of Robert's family, whether you see them or not, we are very close ... and we are all doing everything we can do to bring Robert home."

Burrill and Kerns thanked the more than 2,300 volunteers who helped police search within a 2-mile radius of the Vista neighborhood Friday.

"Yesterday's volunteer search was a major, major step in helping us confirm some (leads), to discount others, and help investigators to narrow their focus," Kerns said.

While the volunteer effort is over, dozens of investigators are continuing to work the case this weekend and follow up all pertinent leads, Kerns said.

"Much of that investigation is happening away from the lens of media cameras," Kerns said. "Trying to find Robert is an hour-by-hour effort."

Burrill continued to ask for community support in the search for her nephew.

"We know the police have to narrow their search, but you may continue to help us by posting fliers, wearing ribbons and continuing to talk about Robert," Burrill said.

Kerns said the Boise police continue to be assisted by all Treasure Valley law enforcement organizations and the FBI.

Many officers are working overtime. Boise police spokeswoman Lynn Hightower said there has been no limit on overtime as Mayor Dave Bieter has told the police to do what they need to do to find the boy.

Patrick Orr: 373-6619