Officers responded about 12:10 a.m. Tuesday to a report of an unresponsive driver who sustained injuries on Pearblossom Highway, east of Highway 18, according to the California Highway Patrol.
The driver was administered life-saving measures but was later pronounced dead at the scene, the CHP said. The name of the victim, a woman in her 20s, was not immediately released.
A passenger in the victim's vehicle said a rock was thrown from an unknown location, authorities said. Investigators searched the location but could not identify or locate a suspect.
"This tragic incident follows another similar occurrence in the vicinity that occurred on the night of Oct. 6, where another driver reported a rock going through their windshield," the Highway Patrol said in a statement.
The rocks thrown at the vehicles in each of those cases are part of an ongoing investigation by the CHP, the agency said.
Anyone with information regarding the rock throwing was urged to call the 24-hour CHP hotline at (323) 259-3200.
City News Service contributed to this report.