SAN FRANCISCO (CBS SF) — Fire officials are investigating whether downed power lines and utility equipment failures may have caused some of the wildfires devastating Northern California’s wine country.

Roughly 22 separate wildfires have consumed approximately 180,000 acres — an area roughly six times the size of San Francisco — in Northern California this week and the causes of those fires remains under investigation.

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While the causes of these historic wildfires have not been officially determined, early 911 calls show people in Santa Rosa reporting blown transformers and downed power lines just as the fires were beginning.

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PG&E was unable to immediately confirm to CBS San Francisco on Thursday which transformers were damaged, when they were damaged and how they were damaged.

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California Department of Forestry and Fire Protection spokeswoman Janet Upton told the Associated Press that it’s unclear whether live wires and downed power lines started the fires or were a result of the fires.

Upton said Thursday that investigators are looking into that, among other possible causes.

Tamar Sarkissian, a spokeswoman with Pacific Gas and Electric Co., told CBS San Francisco, “We aren’t going to speculate on the cause of the fire, but we will support the reviews by any relevant regulator or agency.”

She confirmed that PG&E crews have located downed wires, broken poles and other impacted infrastructure in the area.

Sarkissian said those incidents have been reported to the California Public Utilities Commission and CalFire.

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Sarkissian said Thursday that PG&E is focused on safety and that crews are working to assess damage to the electrical and gas systems that are being impacted by the wildfires.

Since Sunday, 255,218 PG&E customers have lost power in the area and that while 80 percent of those customers have had power restored, about 49,000 — mostly in Sonoma and Napa counties — still remain without power Thursday.

PG&E has also turned off gas to 36,000 customers in the area and is bringing in support from other utilities in Southern Califronia, Nevada, Washington, New Mexico and Arizona.

Sarkissian said that in some cases, winds reached “hurricane strength” at over 75 mph.

“These destructive winds, along with millions of trees weakened by years of drought and recent renewed vegetation growth from winter storms, all contributed to some trees, branches and debris impacting our electric lines across the North Bay,” PG&E said in a statement Thursday.

PG&E said they want the public to know that their “thoughts are with all those individuals who were impacted by these devastating wildfires” and that they are committed to working together during the restoration process.

Cal Fire Director Ken Pimlott spoke about the investigation into the cause of the wine country wildfires on Thursday.

“We’re investigating the fires. And there’s a lot of things in papers, a lot of rumors. Investigators are going right to the cause and the area where these fires started and conducting their investigation using all the tools at their disposal,” Pimlott said. “We’re going to just continue down our path to do that regardless of what’s being said out there. That’s all speculation, all rumor. The facts will come out when the investigations are done…”

With over 3,000 buildings destroyed in the North Bay wildfires this week, if taken as a whole, the wildfires may be the most damaging in the state’s history.

The next most damaging fire in state history, according to Cal Fire, was the 1991 Oakland Hills fire which killed 25 people and burned 2,900 structures.

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By Hannah Albarazi – Follow her on Twitter: @hannahalbarazi.