RIVERSIDE (CBSLA.com/AP) — Officials say nobody was hurt when a Union Pacific freight train carrying automobiles derailed in Riverside County.

Six loaded train cars went off the track along a curve in the Mira Loma area at around 3:20 a.m. Tuesday, according to railroad spokesman Francisco Castillo. All train cars remained upright.

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No injuries and no hazardous materials were involved, according to Castillo.

The derailment occurred near Etiwanda Ave. and Van Buren Blvd. within the Mira Loma Auto Facility, Castillo said.

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The 53-car train was headed to Mira Loma – which is in the city of Jurupa Valley – from Arlington, Texas.

The cause of the derailment is under investigation, according to Castillo.

Metrolink reported delays on its Riverside line due to the derailment.

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