The Karuk Tribe says a massive wildfire burning in a remote area just south of Oregon appears to have caused the deaths of tens of thousands of Klamath River fish.

Tribal fisheries biologists believe a flash flood caused by heavy rains over the burn area caused a massive debris flow that entered the river and sent oxygen levels plummeting to zero.

The Karuk are working with the Yurok, another Northern California tribe, and state and federal agencies to fully to understand what happened.

They say the damage is likely limited to 10 or 20 miles of river.