A fast-moving brush fire that kicked up on a hillside in Northern Nevada just outside Reno on Saturday has exploded to more than 10,000 acres, threatening hundreds of homes.

The Hawk Fire has grown to over 10,500 acres as of Saturday evening, according to the latest update from the National Interagency Fire Center. Local officials said some structures have already burned in the blaze.

Approximately 1,000 homes were threatened, and evacuations have expanded, according to an earlier update from the Washoe County Sheriff’s Office. 

In a statement on social media, Nevada Gov. Joe Lombardo said the fire was “spreading quickly and threatening homes and structures” and said he had declared a state of emergency for Washoe County as firefighters and emergency crews respond to the blaze.

“The Hawk Fire is a very dynamic incident for us as it’s being driven by the winds,” said Truckee Meadows Fire Chief Richard Edwards in a video posted to social media. “The wind-driven fires move very rapidly into our residential areas, creating a lot of challenges for our firefighters to save homes and protect lives.”

He urged residents to pay attention to evacuation orders, leave early if directed and have a go-bag ready.

Earlier, Truckee Meadows Fire & Rescue in Washoe County, Nevada, said the fire was moving Northeast as of Saturday evening, according to a social media post.

Thousands of customers were without power and part of the U.S. 395 highway was closed.

Northern Nevada Health Systems said it had temporarily closed the emergency room at North Valleys north of Reno due to evacuations.

“My heart goes out to anyone in our community who has been impacted by the dangerous and fast-moving Hawk Fire,” Reno Mayor Hillary Shieve said in a statement on social media, urging residents to evacuate if told to do so and saying some structures had already burned.

The statement added: “Our firefighters and first responders are heroically fighting the fire and the high winds to save lives, homes, businesses, livestock and pets.”

The Washoe County Sheriff’s Office said it was monitoring the fire as it burns near the county detention center. 

This is a developing story. Please check back for updates.