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.

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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.

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The driver of the pickup was apparently uninjured.

The circumstances behind the crash weren’t immediately known.

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