LOS ANGELES (AP) — US regulators have ordered the immediate shutdown of a tour bus operator involved in a Southern California crash that killed eight people.

The Federal Motor Carrier Safety Administration said in a statement Friday that the buses operated by Scapadas Magicas LLC pose an imminent hazard to public safety.

On Feb. 3, one of the company’s buses was transporting passengers to Tijuana, Mexico, when it smashed into a sedan, flipped, slammed into a pickup and crashed on a road in the San Bernardino Mountains east of Los Angeles.

Regulators say a post-crash investigation of the company’s two other buses that had been operating in the U.S. found serious mechanical safety violations. The buses were immediately placed out of service.

Inspectors say the company also failed to have its vehicles regularly inspected.

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