Honolulu, HI –

Thursday’s explosion in the State Office Tower turned a utility room into ground zero.

The blast on the mezzanine level blew a machine through a window and buckled a door. Fire investigators say the explosion left enough of a trail to form a theory.

“It appears that gas came in through conduits that were underground along Beretania Street and those conduits exited in that mezzanine,” Honolulu Fire Dept. Capt. Terry Seelig said.

The conduits are pipes that house electrical wiring and communication cables.

“The conduits go up to our equipment room and something in the equipment room must have set off the gas,” State Comptroller Russ Saito said.

“Whatever fire was the result of the explosion was quickly snuffed out or extinguished by the sprinkler system that was in that room,” Seelig said.

That caused some water damage.

The underground conduits sit close to The Gas Company’s four-inch pipe. It delivers synthetic natural gas to buildings along Beretania but not the State Office Tower. So the gas was an intruder.

“We suspect it’s the fiber cable conduit it came in through because the fiber cables go up into the equipment room,” Saito said.

How the leaking gas got into the conduits is still a mystery. About 300 state employees work in the building. They’ve been kept away from their jobs.

“We just want to make sure that everything is in working order before we send people back in,” Saito said.

The Gas Company is using heavy equipment and hand power to repair and relocate the gas line away from the conduits to minimize the chance of future accidents.