The admission by Southern California Edison over its likely role in the Hurst Fire, which did not destroy any structures or result in any deaths, came in a required filing with state utility regulators.

In a second filing, the utility said it is looking into whether an idle transmission line became energised and possibly sparked the deadly Eaton Fire, which devastated Altadena.

But it still maintains there’s no evidence that its equipment was responsible for starting that blaze.

The utility acknowledged last month that fire agencies are investigating whether its equipment may have started the Hurst Fire, which scorched about 3.2 square km around the Sylmar neighbourhood of Los Angeles.

“Absent additional evidence, SCE believes its equipment may be associated with the ignition of the Hurst Fire,” Thursday’s filing said.

The cause remains under investigation and the utility said it is cooperating with investigators.

Regarding the Eaton Fire, SCE said it was reviewing a video that purports to show “flashes” of electrical arcing from a tower near where the blaze began.

The utility said preliminary investigation found no evidence that arcing occurred, while acknowledging that some damage was found on related equipment.

“SCE does not know when this damage occurred and a comparison between pre- and post-fire photographs is underway,” the filing said.

Multiple lawsuits against SCE citing the video claim the utility’s equipment sparked the Eaton Fire, but the utility maintains that it’s still too early to make that determination.

“SCE has not identified typical or obvious indications that would support this association, such as broken conductors, fresh arc marks in the preliminary origin area, or evidence of faults on the energised lines running through that area,” the utility said in a news release announcing its filings.

The Eaton Fire, which killed at least 17 people, was fully contained last week.

Full containment was also reached on the Palisades Fire, the largest of the blazes that destroyed thousands of homes and killed at least 12 people.