Cal Fire says a dozen fires broke out overnight between Friday and Saturday in Eastern Contra Costa County.
The Marsh Complex fires combined to burn 655 acres with containment at 75 percent. The largest of the fires burned 250 acres and threatened some structures. Over 300 firefighters continue to work on containing the three largest fires in the complex.
Authorities said the roadway will be closed between Brentwood and Clayton. It is too soon to know when the area can open back up again.
Some folks in the East Bay received an automated emergency phone call alerting them about this incident, and to shelter-in-place, unless the fire was too close, and they must need to leave.
The area affected included Marsh Creek Road and Morgan Territory Road. Some fires are near the Marsh Creek Detention Facility.
Cal Fire SCU reported that firefighters are on scene of "multiple vegetation fires" west of Brentwood.<
Crews from surrounding agencies responded, including Cal Fire, San Ramon Valley Fire Protection District, and East Contra Costa Fire Protection District.
Arson investigators have been called into to determine what sparked the fires. Authorities are suspicious, since there was no lightning in the area, and the sheer number of the fires raises a concern.
Authorities had recently announced that two-thirds of Contra Costa County are in a fire hazard zone.