A new joint federal-state report on the origin of last year’s wildfire that killed at least 102 people in Maui determined that power lines downed by high winds ignited a brush fire that ended up destroying the town of Lahaina.

The investigation by the federal Bureau of Alcohol, Tobacco, Firearms and Explosives and Maui’s fire department confirms a timeline that Maui residents and news organizations have previously reported.

The ATF report classifies the fire as “accidental.”

The joint investigation doesn’t hold any individual or organization responsible for the fire that caused an estimated $5 billion in damage and left thousands homeless.

A pending $4 billion settlement would resolve hundreds of lawsuits filed by fire victims against the county, Hawaii Electric Company and others.

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At a news conference, Maui Assistant Fire Chief Jeffrey Giesea said, “we want to make abundantly clear to the community that our firefighters went above and beyond their due diligence to be as confident as they could be that the fire was completely extinguished before they left the scene.”

The report released Wednesday says that fire crews responded to a brush fire after 6 a.m. on August 7. About three hours later, the fire was declared 100% contained and the crews left the area.

But less than an hour later, embers from that morning fire rekindled and ignited brush in a nearby gully. The fire soon hopped over a highway and began spreading through the town of Lahaina.

Jonathan Blais, special agent in charge of the ATF Seattle Field Division, said: “I do believe they did everything possible,” to extinguish the fire.

Maui Fire Chief Brad Ventura said his agency continues to educate the community about clearing brush and high grasses and taking other measures to harden their homes against wildfires.