HONOLULU (HawaiiNewsNow) - Investigators with the Honolulu Fire Department interviewed witnesses, inspected the site of the accident, and researched the circumstances surrounding the April 8 explosion and fire at a Waikele storage bunker that killed five men.
On Friday fire Capt. Terry Seelig said HFD reached the limit of what it can do with the information it has.
"We're not able to determine the most probable cause because there's so many possible ignition sources," he said.
Seelig said the point of origin was somewhere in the front of the bunker that held confiscated illegal fireworks. But investigators could not pinpoint exactly where the fire started or what the workers were doing just before the explosion.
"The witness statements can also not be complete enough to give a reliable description of what was going on inside of the bunker," he said.
Killed were Kevin Freeman, Neil Sprankle, Justin Kelii, Bryan Cabalce and Robert Leahey.
The five worked for Donaldson Enterprises. The company finds and clears unexploded ordnance and is licensed to store confiscated fireworks.
"We are not done with our investigation," said Jordan Lowe, agent in charge of the investigation by the Federal Bureau of Alcohol, Tobacco, Firearms and Explosives.
"We're still in the process of trying to determine all of the circumstances surrounding what happened," he said.
The U.S. Chemical Safety Board is also trying to find out what the workers were doing before the explosion.
Relatives of the victims declined to comment for this story.
The fire department's report could be used as evidence in civil or criminal lawsuits
"They have suffered quite a bit," Seelig said. "Their families of course were hoping that there would be some answers here. But this is the best that we can do and we did a very thorough job."
Seelig said there is still explosive material inside the bunker. Messages for the victims are written on the outside walls and a makeshift memorial stands near the locked door.
The fire department's investigation could be reopened if new information is discovered.