A charter bus company involved in a deadly crash in Arkansas last month must immediately shut down because it is an "imminent hazard to public safety," federal officials said Thursday.

A Tornado Bus Co. bus carrying 47 people from Chicago to Dallas crashed along Interstate 40 near Forrest City, Ark., on Nov. 25, killing three people aboard and the driver of a pickup truck that was struck.

Dallas-based Tornado's "motor carrier operation poses an imminent hazard to public safety," according to a Dec. 21 order from the Federal Motor Carrier Safety Administration.

The company's numerous violations "substantially increase the likelihood of serious injury or death to Tornado's drivers, passengers and to the motoring public," the order said.

The order said Tornado needs to be cease all operations because, among other reasons, its practice of permitting drivers to exceed mandated maximum hours of service.

Officials at Tornado did not immediately respond to a phone message seeking comment.

Tornado remains under federal investigation and has been the target of four compliance reviews since 2001.

The reviews have resulted in fines totaling $57,680 for violations that include falsifying driver duty records, according to the safety administration.

Routine roadside inspections have resulted in another $5,140 in fines for other violations.

The order allowed vehicles to continue to their next scheduled stop so passengers could be safely accommodated, but no additional passengers could be loaded.

Tornado's Web site is in English and Spanish and touts its routes to Mexico. It also advertises routes from Georgia, North Carolina, Illinois, Florida, Tennessee and Texas.

Tornado is at least the second Texas-based bus company ordered shut down since 2005. Federal regulators shut down Global Limo after a 2005 bus fire killed 23 nursing home patients fleeing Hurricane Rita.

Global Limo's owner was convicted last year of poorly managing his fleet and not requiring drivers to fill out vehicle inspection reports. None of the charges were directly related to the deadly bus fire.