GROVELAND, Calif. (AP) — The giant wildfire burning at the edge of Yosemite National Park has not only destroyed buildings and threatened water supplies, electricity and sequoias, it has also unleashed a smoky haze that has worsened air quality more than 100 miles away in Nevada.

The plume from the Rim Fire in California triggered emergency warnings in the Reno and Carson City area. Schoolchildren were kept inside for the second time in a week, people went to hospitals complaining of eye and throat irritation and officials urged people to avoid all physical activity outdoors.

“It’s five hours away,” said 22-year-old bartender Renee Dishman in disbelief after learning that the source of the haze was more than 150 miles away. “I can’t run. I can’t breathe. It makes me sneeze.”

The Rim Fire, so far, has burned through 280 square miles, destroyed 23 structures and threatened water supplies, hydroelectric power and giant sequoias. On Tuesday night, authorities said the blaze was 20 percent contained.

In Nevada, the biggest impact of the Rim Fire was on the air. The air quality index briefly surpassed the rare “hazardous” level east of Lake Tahoe before improving slightly. It hovered around the next-most serious stage of “very unhealthy” for all populations in the Reno-Sparks area 30 miles north.

Dennis Fry, a Reno auto body specialist for nearly 30 years, remembered smoke this thick when he worked on a logging crew and helped fight fires in Oregon during the 1970s.

“But never in Reno, not this bad,” he said. “You could actually see the smoke inside my body shop.”

Everyone should avoid all physical activity outdoors when the air quality index reaches “hazardous,” considered “emergency conditions,” the Nevada Division of Environmental Protection said on its website. “People with heart or lung disease, older adults and children should remain indoors and keep activity levels low.”

Renown Regional Medical Center in Reno has experienced a “slight increase” in emergency room visits as a result of the smoke, said Jennifer Allen, the hospital’s clinical nursing supervisor.

“Patients are experiencing shortness of breath, eye and throat irritation, cough and headache due to the heavy smoke and poor air quality,” she said.