HERCULES -- An unidentified woman died Monday afternoon after she rear-ended a van while driving westbound on Highway 4 and crashed into a field at a high rate of speed, according to the California Highway Patrol.

About 5:28 p.m., the woman was driving a blue Hyundai Tucson SUV just east of Willow Avenue when she rear-ended a Honda Odyssey van, CHP Officer Peter Van Eckhardt said. The driver of the Honda pulled over to the side of the road to exchange information, at which point the SUV continued past and lost control.

According to Van Eckhardt, the SUV did not get far before it crashed through a guard rail and out into a field, about 100 feet off the roadway. The woman in the SUV was pronounced dead at the scene.

No one else was in the SUV with the woman, and the driver of the Honda was uninjured, Van Eckhardt said. The investigation into the crash is ongoing.

Contact Erin Ivie at eivie@bayareanewsgroup.com. Follow her at Twitter.com/erin_ivie.