RICHMOND -- A 28-year-old woman is clinging to life after she was struck by a car while standing in the middle of Interstate 80, a crash witnessed by four young children, authorities said.

The Richmond resident was flown by helicopter to John Muir Medical Center in Walnut Creek with major injuries following the Monday night crash, according to Officer Sean Wilkenfeld of the California Highway Patrol.

The woman was feeling drowsy and struck the median on westbound I-80 near Solano Avenue to avoid hitting a car in front of her at around 9:20 p.m., Wilkenfeld said. Her Ford stopped in the fast lane, and the woman got out and stood in the next lane to call for help, the CHP said.

Moments later, a driver swerved to avoid hitting the Ford, where four young children and an adult passenger were seated, authorities said.

The car instead struck the woman standing in the middle of a lane. No one else was seriously injured.

David DeBolt covers breaking news. Contact him in Richmond at 510-262-2728. Follow him at Twitter.com/daviddebolt.