'Accidental causes' likely in Oceanside Pier fire: officials

OCEANSIDE, Calif. (FOX 5/KUSI) -- The fire that burned part of the Oceanside Pier last week likely started from "accidental causes," officials said Monday, adding that there was no evidence it was intentionally set.

The blaze broke out on the end of the pier Thursday afternoon, ripping through a former Ruby's Diner and sending a large plume of black smoke billowing overhead. Firefighters battled the flames for several hours and, after a period of subsequent smoke, deemed the fire completely out early Monday.

Oceanside Fire Chief David Parsons shared investigators' preliminary findings during a news conference Monday, opening with the discovery that the blaze started on the northwest corner of the pier, outside of the restaurant building.

"No evidence of an incendiary or intentional act was found," Parsons said, adding that an accelerant-detection K9 from the Bureau of Alcohol, Tobacco and Firearms searched the area and found "zero hits and zero interest."

Parsons added that due to the weather conditions that day -- no lightning, for example -- investigators were able to rule out natural causes. By "process of elimination," investigators are left with "accidental causes" as the most likely explanation, Parsons said.

"But that doesn't mean we can necessarily say it was one thing or another, because you have to have a particular device identified that may have failed, and due to the fire and due to potentially falling in the ocean, we're not able to get there," Parsons said.

What investigators can't rule out is an electrical heat source, Parsons said. A formal investigation report is likely weeks away, pending potential lab testing and samples, and more interviews, the chief added.

Just north of the inactive restaurant was a smaller eatery, Brine Box, where two employees were working at the time of the blaze, Parsons said. While that business was using the kitchen of the former diner for prep, they were not cooking there. Parsons said the sole heat source at the vacant restaurant was a hot plate occasionally used to make hot chocolate, and it was not in use Thursday.

All employees were accounted for and no injuries were reported, according to Oceanside Mayor Esther Sanchez.

Parsons said video evidence and witness interviews "point to something going on outside the building and potentially under the deck." And while investigators have identified the northwest corner as an area of origin, they were still searching for a point of origin, though the extent of damage to the pier may prohibit that finding, Parsons said.

Between 90% and 95% of the wooden pier was saved, and damage was limited to the structure's "hammerhead" -- the end of the pier where the former diner was located, Oceanside Deputy Fire Chief Jess Specht said.

Swimmers and surfers have been cleared to use the water in the area if they stay more than 100 feet from the pier, said Oceanside Lifeguard Sgt. Jonathan Chester. Boaters were advised to stay 100 yards from the structure.

The pier itself has not been reopened to the public. Blake Dorse, division chief with Oceanside Fire Department, said officials hope to open 75% of it "as quickly as possible."