(This story was updated to add video and more information from fire officials.)

Fire crews were responding to a brush fire Monday night near Auto Center Drive in Ventura.

The Ventura fire was first reported in the Santa Clara River bottom around 6:50 p.m. as Santa Ana winds whipped through the region.

As of 9:30 p.m., an evacuation order had been issued for the Santa Clara River between the 101 Freeway and Victoria Avenue.

“No residential structures are under evacuation at this time,” according to Ventura County’s emergency services site https://www.vcemergency.com.

Homeless encampments dot the riverbed, and some commercial businesses surround the area where the fire first erupted.

By about 8 p.m., the Auto Fire, as it’s called, was pegged at 5 acres, according to initial fire reports. Ground crews and helicopters quickly rushed to the area, making water drops.

Shortly before 9 p.m. about 75 firefighters were working on the fire, which was described as being in medium fuel and moving at a moderate rate of speed, according to Ventura County Fire on social media.

More air support had been requested, and by 9 p.m. a helicopter from Los Angeles County appeared to be on its way, according to radio traffic.

Traffic along Victoria Avenue, which runs through both Ventura and Oxnard, was being shut down between Gonzales Road and Olivas Park Drive. as onlookers snarled traffic and made access more difficult.

By 9:30 p.m., an estimated 100 firefighters were battling the blaze in 10-11 acres.

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At one point early on, the fire had reached into RiverRidge Golf Club across the river in Oxnard. Radio traffic indicated the course superintendent planned to put on the sprinklers.

A second fire in Simi Valley was reported at 7:48 p.m. The fire, dubbed the Royal Fire, ignited in the central part of the city near Darrah Volunteer Park and the Arroyo Simi Equestrian Center, according to initial fire reports.