Fire investigators now believe the fire that coursed through 20 acres in the Berkeley and Oakland hills may have been arson.

By Frances Dinkelspiel and Natalie Orenstein

Update, Aug. 5, 11:20 a.m. The wildland fire in the East Bay hills has transitioned into “patrol status,” meaning a reduced number of crews will spend the next few days checking the area for remaining hotspots, according to the Alameda County Fire Department. Once an operation involving several agencies, the fire fight will now be handled by Oakland and East Bay Regional Parks District fire departments.

All roads and trails in the area are open this weekend, said East Bay Regional Parks District spokesman Dave Mason on Saturday morning.

Just before midday Saturday, groups of people were at the Grizzly Peak look-out areas, including at Signpost 15 where the fire originated, taking in the views as well the burnt-out areas of the hills with charred remains of trees and soot.

Update, Aug. 4, 8 a.m. The wildfire that spread through the East Bay hills beginning Wednesday afternoon is now 70% contained, said Oakland Deputy Fire Chief Melinda Drayton on Friday morning. Crews worked all through the night, and 75 firefighters, scaled down from around 150 on the scene Thursday, will continue extinguishing hotspots today.

The multiple agencies tackling the fire are “hoping to wrap up by 8 p.m.,” Drayton said.

Grizzly Peak Boulevard is still closed to traffic between South Park Drive and Centennial.

Original story, Aug. 3, 4:08 p.m. While fire crews are still putting out hotspots in the wildfire along Grizzly Peak, officials are now investigating whether the fire was deliberately set.

Sgt. Sabrina Reich of the UC Berkeley Police Department said in an email that the origin of the fire that broke out around 1 p.m. on Wednesday may be suspicious.

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“We are investigating the fire as a possible arson,” Reich wrote.

Cal Fire is taking the lead in the investigation.

The fire burned around 20 acres in the Berkeley and Oakland hills along Grizzly Peak Boulevard just north of South Park Drive. Nine agencies responded to the fire and about 150 to 200 fire fighters have worked many hours to put out the fire in the dense brush. Tree fellers arrived this morning, ultimately chopping down three hazardous trees, said Oakland Deputy Fire Chief Melinda Drayton at a press conference at the scene at 4 p.m.

The fire has been about 50% contained since the morning, according to Oakland fire officials. It has not spread since 9 p.m. Wednesday night. Crews will continue to work through the night.

“We’re still working on extinguishing hot spots, working the perimeter and taking down trees,” Drayton said.

OPD investigating other incidents along Grizzly Peak

The Oakland Police Department is meanwhile investigating incidents that occurred in the same area Wednesday morning, before the fire started.

Around 8 a.m., OPD responded to a collision on Grizzly Peak, just west of Fish Ranch Road, according to a release sent out on Thursday. The driver of one of three cars “brandished a firearm at an involved vehicle, then returned to their vehicle and fled the scene,” the release said. The other two cars remained at the site, and there were no injuries reported.

Officers returned to the scene around 11 a.m., receiving reports that the suspect was back in the area. They found the suspect’s abandoned car further west on Grizzly Peak. Berkeleyside’s Frances Dinkelspiel was at the scene of the fire on Wednesday, where the car was still parked on the hill.

The suspect then reportedly entered Lawrence Berkeley National Lab property, causing a lockdown across the lab. UC Berkeley police later arrested the suspect, and OPD is now handling the case. The UCPD crime log shows the suspect was arrested on suspicion of both vehicle theft and arson, specifically “starting a wildland fire,” as first reported by The Daily Cal.

However, the OPD statement said, “At this time, the Oakland Police Department investigation has not determined that the suspect arrested by the University of California Police Department on August 2, 2017 is connected to the Oakland fire on Grizzly Peak Boulevard.”

This story was updated as new information became available.