FRESNO COUNTY, Calif. (KSEE/KGPE) - Four people were killed in a traffic collision Friday night, and alcohol and/or drugs are believed to be a contributing factor, the California Highway Patrol said. Just after 10:30 p.m. Friday, officers were dispatched to a report of a crash at Floyd and Shaw Avenues, east of Biola.  They say they arrived to find a Ford Econoline van and a Nissan Altima had violently collided in the intersection. Investigators say the person driving the Ford was traveling southbound on Floyd Avenue and had stopped at the stop sign at Shaw Avenue, but then proceeded into the intersection as the Nissan traveled westbound on Shaw Avenue. That's when the two vehicles came into contact with one another, causing them both to veer off the roadway and onto the southwest shoulder of the intersection. Officers say the force was so great that the crash ignited both vehicles on fire. Two male passengers in the Altima, ages 32 and 35, were able to self-extricate before their vehicle became engulfed in flames.  Both those men were treated for moderate injuries at the scene. The CHP says the driver and one of the Ford's passengers, as well as the driver and an additional passenger of the Nissan, all died of their injuries at the scene. The California Highway Patrol is seeking the public’s assistance as it gathers information about the crash. Anyone with information is urged to contact the Fresno-area CHP at (559) 262-0400.