An unidentified 23-year-old woman from Santa Ana died after she was thrown from a late-night collision on the I-5 freeway when a driver rear ended a big rig, according to the O.C. Register.

Steven Heemstra, 24 of Irvine, was driving a gray 2013 Honda Civic at around 11:30 p.m. on the southbound I-5, south of First Street, when he crashed into the back of Idolina Romo’s big rig truck, according to the CHP.

The CHP did not report why Heemstra rear-ended the truck.

The crash resulted in a 23-year-old Santa Ana woman being tossed from the Honda Civic. She was pronounced dead by Orange County Fire Authority paramedics on the freeway, according to the O.C.F.A.

CHP investigators reported that the victim was not wearing a seatbelt.

Heemstra ended up at the Orange County Global Medical Center, in Santa Ana, with serious injuries.

The truck driver, Romo, was not hurt in the accident.

So far the O.C. Coroner has not identified the Santa Ana woman.