TWISP, Wash. — Reduced winds on Saturday helped firefighters gain the upper hand against a series of giant wildfires in north-central Washington that earlier left three firefighters dead.

The Okanogan Complex of wildfires was measured at 355 square miles on Saturday, about 100 miles larger than Friday, fire spokesman Rick Isaacson said.

But the flames were moving away from population centers in Okanogan County.

Thousands of people in the county remained under evacuation orders.

Resources were so strained that on Saturday fire officials began providing basic fire training to volunteers who have machinery like backhoes and bulldozers so they can help dig fire lines.

Meanwhile, a second of the four firefighters injured in a wildfire Wednesday has been transferred to Harborview Medical Center in Seattle. A Harborview spokeswoman said Saturday that the firefighter is listed in satisfactory condition.