RIPON – The California Highway Patrol says two farm workers were killed and six injured after their van struck a big rig and rolled.

The driver, 21-year-old Ambrosio Martinez of Merced, was passing the semi truck early Wednesday to exit Highway 99 in Ripon, south of Stockton.

The van clipped the semi truck, rolling several times. Two men and a woman were not wearing seatbelts and were ejected. CHP Officer Adrian Quintero says one man and the woman died at the scene.

The driver survived and may face charges.

The names of the dead and injured farm workers were not immediately released.

It was the second fatal farm worker crash in California this month.

Six workers from Lodi died July 15 when their vehicle drove into a Central Valley canal after colliding with a septic truck. The truck's driver also died.