FAIRFIELD (CBS SF) -- A fast-moving brush fire in Solano County has burned over 4,500 acres and two structures, including a house, near Suisun City, according to Cal Fire.
The four-alarm blaze, first reported near Highway 12 at 10:46 a.m., was not under control as of 1 p.m., according to a Solano County Sheriff's Department dispatcher.
No evacuations have been ordered but at least one structure has burned in the fire. The marshy area is sparsely populated; there are a few homes and other buildings.
In the area where the fire burned, there are duck clubs where hunters set up in blinds and wait for their prey. At least one building associated with a duck club has burned down.
Whipping winds of 40-50 miles per hour were pushing the fire away from Suisun City and into the Delta, toward the Sacramento River, according to a post by the Suisun City Fire District's Facebook page.
Travis Air Base officials told KPIX 5 that they are still trying to determine the origin of the fire, which they believe started either on on near the base. The blaze jumped from near the air base over Highway 12.
Firefighters from multiple agencies in the region have sent crews to the blaze, including crew from Suisun City, Montezuma, Benicia, American Canyon, Vallejo and Travis Air Force Base.
At one point, the fire closed down Highway 12 near Branscombe Road in Solano County, according to the California Highway Patrol.
Smoke from the blaze was blown throughout the East Bay and parts of the South Bay due to northerly winds, according to Kristine Roselius, communications director of the Bay Area Air Quality Management District.
"Smoke from this fire is all the way down into Contra Costa County and Alameda County. What's burning here is just annual grassland. It's been very dry and with the wind pushing it, it's burning very hot and very fast," said Dennis Rein of Suisun Fire Protection District.
Several police and fire departments throughout the region received inquiries from residents concerned by the heavy smoke. Air quality officials and local fire and police departments are warning affected individuals to stay indoors.
Due to the high volume of smoke, the Bay Area Air Quality Management District has declared an air quality advisory throughout the Bay Area through Monday.
Police and fire departments urged residents to refrain from calling 911 to report the smoke and to stay vigilant for any actual fires.
Red Flag conditions will continue through Monday for most of the Bay Area, according to the National Weather Service.
The Solano County Salvation Army is keeping firefighter crews fed and hydrated.
As of 7:45 p.m. Sunday evening, Solano County Sheriff's Office reported that the fire was 70% contained. Officials felt comfortable enough to release the crews that came from outside of Solano County to battle the fire.
An earlier brush fire in Solano County briefly shut down Interstate 505, including connector ramps to Interstate 80 in Vacaville.
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