The California Highway Patrol is investigating the cause of the accident that sent two others to the hospital, including an off-duty Contra Costa County sheriff's deputy, said CHP spokesman Scott Yox.
The accident involved a Saturn sedan being driven by the 45-year-old San Francisco County deputy, a Honda CR-V driven by the Contra Costa County deputy and a GMC pickup truck driven by a 52-year-old Antioch man, Yox said.
The No. 1, 2 and 3 lanes were blocked and only the No. 4 lane was open to traffic as of about 11 a.m.
The CHP is looking for the public's help in determining what caused the accident, said Yox. Anyone who may have seen any of the involved vehicles before, during or after the incident is asked to call the CHP tip line at (800) TELL-CHP or the Contra Costa County sheriff's dispatch line at (925) 646-2441.
"Even the smallest detail can help us with this investigation," Yox said from the scene.
