GILROY -- One person is dead and traffic has slowed to a crawl after a head-on collision left all but one lane closed Tuesday evening along Highway 152, according to the California Highway Patrol.

The crash was reported at about 5:30 p.m. on Highway 152 near Highway 156. According to the CHP, several drivers called to say a red 1995 Hyundai Accent was swerving in and out of traffic and nearly hit a retaining wall before it slammed into a big rig just west of San Felipe Road.

The driver of the Hyundai, who has not been identified, was declared dead at the scene. The driver of the big rig did not suffer any injuries.

No one else was injured.

Traffic was at a crawl just after 6 p.m. when CHP officers closed all but one lane in both directions along Highway 152. Officers were able to reopen lanes around 9:08 p.m.

The cause of the crash remains under investigation.

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