The Kern County Fire Department responded to calls for a grass fire near Highway 58 and Highway 223 Friday morning. 

Fire crews found a two-acre fire that was spreading up the hillside from the freeway frontage road. Access issues and a threatened building caused a task force of patrols and wild land fire engines to protect the building. 

Favorable weather conditions and an aggressive attack by ground and air resources kept the fire to about 40 acres. About 30 percent of the fire had been contained as of Friday afternoon.

During the initial stages, there were four air tankers and two helicopters used to fight the fire. Fire crews will remain on scene through the night to continue containing the fire and cool hot spots. 

The cause of this fire is under investigation. No injuries were reported.