The federal order prohibits the company from resuming interstate or intrastate operations until its has met a series of stringent conditions, including coming into compliance with federal trucking regulations and identifying the reasons for its past violations. The agency said the company must prepare a plan to retrain its drivers and "take immediate, aggressive and progressive steps to control drivers' hours of service."

The motor carrier administration, which in the past has had problems with companies it has ordered off the road going back into business under other names, is also seeking to close that escape route in this case. Its order specifies that Gunthers cannot avoid the order by continuing operations under another name, including those of current affiliates, and forbids it to sell or lease its equipment without agency permission.

Willful violations, the agency said, can result in both civil and criminal penalties.

The trucking association's McNally said the industry welcomes such actions against serious violators.

"The agency is doing its job by taking this type of enforcement action against rogue trucking companies," he said.

The announcement of the sanctions came the same day the trucking association criticized the motor carrier administration for not calling much attention to its own statistics showing that the safety record of the industry is improving.

The association pointed to figures showing a 31 percent decrease in fatal crashes involving large trucks between 2007 and 2009. The same report showed a 31 percent drop in injury-causing crashes over that time and a decrease in the rate of fatal crashes from 1.1 per 100 million miles in 2008 to 1 per 100 million in 2009.

"Truck drivers are driving more miles and having less crashes," McNally said. "The highway is their office, so they have an interest in improving safety."

The motor carrier agency is headed by Anne S. Ferro, a former head of the Maryland Motor Vehicle Administration and former president of the Maryland Motor Truck Association.

"FMCSA has zero tolerance for unsafe trucking companies that place the traveling public at risk. If they do not play by the safety rules of the road, we will take away their ability to operate," Ferro said.

Baltimore Sun reporter Peter Hermann contributed to this article.