Fire investigators are not yet ready to declare the origin of the Darlene 3 wildfire near La Pine in central Oregon except to say that it was “human caused.”

On Sunday, the 3,889-acre fire — sparked Tuesday, when there were no reports of lightning — was 60% contained, and fire crews stood at 304 personnel, down from a peak of 435.

Kaitlyn Webb, a spokesperson for the Central Oregon Fire Management Service, said Sunday that the fire’s cause remained under investigation and there was no timeline to announce any results.

Social media users, meanwhile, have connected the fire to encampments in Deschutes County. Webb would not comment on those reports. “We are aware of those videos,” Webb said.

She added only: “We know it was human caused.”

— Beth Slovic is a deputy editor on the public safety and breaking news team. Reach her at 503-221-8551 or bslovic@oregonian.com.

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