(CNN) — Nearly a million acres were burning as 21 wildfires raged in the Pacific Northwest on Sunday, fire officials said.
The unconfined fires in Oregon and Washington, mostly ignited by lightning from thunderstorms that swept through the region a week ago, covered 942,247 by Sunday, Northwest Interagency Coordination Center spokeswoman Carol Connolly said.
The 21 large fires are the most the region has seen on the landscape at one time, she said.
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Firefighters from across the United States, including Mississippi, Illinois, New Mexico, Utah and Montana, have joined the battle, bringing to 8,928 the number of people involved in trying to contain the fires, Connolly said. There are 35 “hot shot” crews involved, she said.
Flames have destroyed at least 132 structures, but no lives have been lost, Connolly said.
Health officials in Washington and Idaho are warning residents that smoke drifting eastward from the Washington wildfires would create unhealthy air.
“The biggest health threat comes from the fine particles in smoke,” the National Weather Service said. “These can cause burning eyes, runny nose, bronchitis and other illnesses. Smokey air can also aggravate heart and lung disease, and even lead to death.”
CNN’s Janet DiGiacomo contributed to this report.
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