A two-alarm brush fire burned about five acres next to U.S. Highway 101 in the Marinwood and Novato area Sunday, a fire chief said.
The fire was reported around 11:10 a.m. in a grassy area just off of a bike path that runs alongside southbound Highway 101 in the unincorporated community of Marinwood, according to San Rafael fire Chief Christopher Gray.
The blaze spread quickly up a hillside and threatened several homes in the area, but firefighters' aggressive attack kept it from spreading further, the chief said.
Cal Fire helicopters were called to dump water on the blaze and firefighters were able to contain the fire a short time after noon, Gray said.
Crews from Cal Fire as well as the San Rafael, Novato and Marin County fire departments responded to the scene. The cause of the fire is under investigation.
Gray said the fire is "another wakeup call about the severity of this fire season."
Fire departments are asking residents to do their part by clearing brush around their homes to create a defensible space.
"It not only helps the homeowner, it helps firefighters, too," the chief said.