MARTINEZ -- One person was killed in a solo vehicle crash on Highway 4 early Saturday, a California Highway Patrol dispatcher confirmed.

The accident was reported around 5:33 a.m. and CHP officers had to shut down the eastbound Pacheco Boulevard on-ramp around 5:47 a.m. while crews investigated the scene.

The identity of the driver who was killed was not available.

The cause of the crash is under investigation. No one else was injured, the CHP dispatcher said, and the eastbound Pacheco Boulevard on-ramp was reopened by 7:30 a.m.

Check back for updates.

Staff writer Kristin Bender contributed to this report. Contact Katie Nelson at knelson@bayareanewsgroup.com and follow her at Twitter.com/katienelson210.