Investigators are trying to figure out what led to a traffic accident in Ventura County which left two people dead and two seriously injured. The accident happened just after 8 p.m. Tuesday, on Pleasant Valley Road near Longfellow Way in Oxnard. Police say the pickup was speeding westbound on Pleasant Valley Road when the driver apparently lost control of the vehicle, and smashed into an electrical pole and a tree. The driver, identified as Mario Gurrola of Port Hueneme, was pronounced dead at the scene. Paramedics were also unable to save passenger Luis Fernando Hernandez of Oxnard. The other two passengers are expected to recover from their injuries.