Gene Blevins / Reuters

A San Bernardino firefighter looks at the scene where a least eight people were killed and dozens were injured when a tour bus crashed Feb. 4.

Published 10:30 p.m. ET: U.S. regulators ordered the immediate shutdown of a tour bus operator involved in a deadly tour bus crash on a mountain road in San Bernardino County last weekend.

The Sunday evening crash killed at least eight people, including seven tour bus passengers and a pickup driver who was struck by the bus as it careened out of control on Highway 38 near Yucaipa. Dozens of people were injured in the crash, some of them critically.

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.

Read the order and more at NBCLosAngeles.com

A bus operated by the company was transporting passengers to Tijuana, Mexico, on Sunday when it smashed into a sedan, flipped, slammed into a pickup and crashed on a road in the San Bernardino Mountains.

A post-crash investigation of the company's two other buses that had been operating in the U.S. found serious mechanical safety violations, regulators said. The buses were immediately placed out of service.

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

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