Crews battling the Diablo Fire near Byron have the blaze 100% contained on late Sunday afternoon, Cal Fire said.
The brush fire was reported about 9:20 a.m. near Vasco Road and Camino Diablo in Contra Costa County.
The blaze had burned 128 acres and was 100% contained, Cal Fire said on social media about 4:20 p.m.
No injuries have been reported and no structures have been damaged. The cause is under investigation.
Assisting Cal Fire in the firefight are the Alameda County, Contra Costa County, East Contra Costa and East Bay Parks fire departments.