CORONA (CBS) — A motorist involved in a two-car crash south of Corona Monday was hospitalized in grave condition, authorities said.

The collision happened around 5 p.m. at Cajalco and Temescal Canyon roads, just off Interstate 15, according to the California Highway Patrol.

Riverside County sheriff’s deputies were first to arrive at the scene and reported that the driver of a Ford Focus was in full cardiac arrest after his vehicle was struck by a pickup truck.

Corona fire paramedics rushed the motorist to Riverside Community Hospital.

The driver of the pickup was apparently uninjured.

The circumstances behind the crash weren’t immediately known.

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