The two Contra Costa County Sheriff's deputies involved in an that left their patrol vehicle upside down on Interstate-680, just north of El Pintado, got out of there with only minor injuries, California Highway Patrol officer John Fransen said.
The deputies, one male and one female, were taken to a local hospital but for precautionary reasons only, he added.
The accident is still pending investigation, but Fransen said that "evasive action" the driver took in order to avoid a collision with the car in front of it lead to the incident.
At 1:52 p.m., the patrol vehicle, he said, was traveling in the lane to the right of the HOV lane at approximately 65 mph when the car in front of it abruptly stopped.
"The driver of the patrol vehicle took evasive action and changed lanes to the (HOV) lane," Fransen said. "Unfortunately the patrol vehicle lost control and traveled across all lanes, from the (HOV) lane onto the dirt embankment where it overturned."
The accident closed all but one lane on northbound I-680, clogging traffic back to Alcosta for nearly two hours after the accident took place.
Traffic was diverted through downtown Danville and cars were "bumper-to-bumper," one Danville Patch reader posted on Danville Patch's Facebook page.