A driver was killed after losing control of her car on Interstate 680 south of Pleasanton and overturned multiple times down a hill next to the freeway on Sunday morning, according to the California Highway Patrol.

The 24-year-old woman behind the wheel was the only occupant of the vehicle, according to CHP Officer Tyler Hahn. Her name has not yet been released publicly.

The situation unfolded at approximately 10:40 a.m. Sunday when a black Mazda 3 traveling southbound on I-680 in the far-left lane lost control just south of the Happy Valley Road underpass in Pleasanton, according to Hahn.

The car drifted into the center divider on the left and then went across all lanes to the right before going off the freeway down a dirt embankment. The car overturned a few times before landing on its tires about 75 feet down the hill, Hahn said.

Cal Fire personnel pronounced the driver dead at the scene.

The cause of the crash remains under investigation. "Witnesses say the vehicle was not hit by another vehicle or cut off to make it go down the embankment," Hahn said.

Anyone who may have information about the fatal crash can contact the CHP-Dublin office at 925-828-0466.