HUNTINGTON BEACH – A woman was hospitalized early Wednesday morning after an explosion in a storage unit, officials said.

At least two Huntington Beach police officers heard “a significant explosion” at 5:26 a.m. about a half-mile away at Huntington Beach Propane, 18961 Gothard St., fire Battalion Chief Jeff Lopez said.

The officers rushed to the location, which also houses about 100 metal shipping containers that are rented out as storage units, and found a woman who works and lives at the business buried underneath a pile of smoldering rubble, fire Capt. Bob Culhane said.

“They brought her out to the sidewalk, just to get away from it because they weren’t sure if there was going to be a second explosion,” Culhane said.

Paramedics then rushed her to Santa Ana’s Orange County Global Medical Center in an unknown condition.

The woman lives in an RV at the location with a man, and they both work as nightwatchmen for the facility, Lopez said.

Although the business houses flammable propane, that was not a factor in the explosion, Lopez said.

“The explosion involved one of the storage containers, and not the propane on site,” Lopez said. “There may have been a small propane tank in the storage container, but we don’t know that.”

Officials said the woman was likely close to the unit at the time of the mysterious explosion, according to witness reports.

“The nightwatchman said … someone was in or around the storage container when it exploded,” Lopez said.

“The explosion damaged two nearby vehicles, a block wall, and two other Conex boxes,” according to a Fire Department release. “The involved container is still intact but is significantly deformed from the force of the explosion.”

Arson investigators remained at the scene after daybreak trying to determine what caused the blast and the possible criminal intent, but there was no public safety concern.

“It was just kaboom and then it was done,” Lopez said.

Authorities would not comment about the woman injured in the explosion and refused to update her condition, citing health record privacy laws.

The window of a nearby business was also damaged in the blast, but no one else was injured, police said.

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