EL CAJON, Calif.—An investigation was continuing Dec. 19 into the cause of a two-vehicle crash on the 8 Freeway in El Cajon that killed a 32-year-old woman from Lemon Grove.

The collision on the eastbound highway at the Second Street off-ramp occurred about 4:30 a.m. Dec. 18, according to the California Highway Patrol. The woman was driving a 2002 Audi TT eastbound on the freeway west of Second Street, just as a second driver in a Honda CRV was on the off-ramp to Second Street, officer Matthew Baranowski said.

For unknown reasons, the Audi driver “allowed her vehicle to travel off the roadway, where it struck a tree before colliding into the Honda” and died at the scene, Baranowski said.

At least one vehicle caught fire during the crash, the agency said.

The Honda driver, a 31-year-old man from El Cajon, and a 51-year-old passenger, also an El Cajon resident, sustained minor injuries and were treated at the scene, Baranowski said.

The crash was still under investigation. It was unclear if drugs or alcohol were a factor, Baranowski said.

The county Medical Examiner’s Office will publicly identify the woman pending notification of family.