Three months after someone torched part of University Laboratory School, no one has been arrested and police have no viable leads.

Investigators are now re-interviewing witnesses and double-checking evidence to make sure they haven't missed anything.

"What they're doing now," said Honolulu police spokesman Capt. Frank Fujii of the investigators, "is backtracking, going over what they have. Backtracking involves re-interviewing witnesses and neighbors with the hope they can corroborate evidence from the scene."

Fujii declined to say how the fire was started, how many people police have interviewed and if anyone is under suspicion.

Six days after the June 13 fire, police announced that it was intentionally set. They said witness statements, burn characteristics and the exclusion of accidental causes led them to open an arson investigation.

Detective Gary Lahens, the lead investigator in the case, told The Advertiser in July that police were investigating reports that people were seen outside the 'ewa side of the 67-year-old building where the fire started. He declined to elaborate then and was unavailable for comment yesterday.

WITNESS TIPS VITAL

The case is being investigated as first-degree arson, which is punishable by up to 15 years in prison and a $50,000 fine.

In another arson investigation, police on Tuesday announced they had arrested two 13-year-old boys in connection with the Sept. 12 fire at the Church of Jesus Christ of Latter-day Saints in Wai'anae. The fire caused $2.5 million in damage.

Lahens also was the lead investigator in the church case.

Tips led to a break in the Wai'anae case, Fujii said. But no viable tips have come forward in the Lab School investigation.

"Whether it's murder or robbery, things have to fall in place to corroborate evidence and a big part is witnesses coming forward," Fujii said.

Public help is a major factor in arresting arson suspects, said Glenn Solem, a retired captain who supervised Honolulu Fire Department's fire investigations.

"People in many areas, for example, Wai'anae and Nanakuli, have become more forthcoming about reporting rather than protecting individuals," said Solem, head of Hawaii Fire Dynamics LLC, a private investigation and consulting firm.

'TRAINING IS BETTER'

Without that public assistance, cases are more difficult to make. One difficulty, he said, is proving intent. A lot of expertise is required to connect evidence to the suspect, for example.

Investigators these days do have better technology and training, however.

"The training is better and there's more scientific input and testing of materials that allows (investigators) to come to better and more concrete conclusions," he said.

Honolulu police have a lab that can test evidence for ignitable and combustible liquids, such as gasoline, Solem said. The fire and police departments are also discussing whether to acquire an accelerant-sniffing dog, which could pinpoint where samples should be taken at a fire scene to determine if the fire was deliberately set, he said.

University of Hawai'i spokesman Jim Manke said the school did not want to comment during the investigation.

Reach Rod Ohira at rohira@honoluluadvertiser.com.