Correction: An earlier version of this artilce incorrectly said that bus companies rival airlines in carrying about 700,000 passengers a year. The bus and airline industries each carry about 700 million passengers a year. This version has been corrected.

A Virginia State Patrol cruiser sits in front of the aftermath of a May 2011 early-morning bus crash that killed four people, in the northbound lanes of Interstate 95 in Carmel Church, Va. (JONATHAN ERNST/REUTERS)

Some of those sleek, modern curbside buses that pass through Washington en route to other East Coast cities may be operated by sleepy, untrained drivers and running on bad tires and worn-out brakes, federal officials said Thursday as they ordered more than 30 of the vehicles off the road.

The crackdown targeted three companies that operate under more than two dozen names, carrying about 1,800 passengers a day along the Interstate 95 corridor between New York and Florida.

Authorities said the companies have evaded federal efforts by playing another common curbside trick: the shell game. Whenever they were shut down, the companies resumed business under another name.

“They’ve slapped another name on the side of the bus and started driving again,” said U.S. Transportation Secretary Ray LaHood. “These buses are not on the road today, and we’re going to focus like a laser beam in making sure they don’t get back on the road.”

Not among the well-known carriers such as BoltBus or Vamoose, they have been called “ghost” companies because their buses often are stark white, unadorned by brand names.

The growth of the low-cost companies has been evident on the streets of the District, where people congregate to await their arrival at established locations in Chinatown and elsewhere. Nationwide, bus companies rival the airlines in carrying about 700 million passengers a year, and their fares often are far less than the cost of gas and tolls for trips between major cities.

The most common destinations from the Washington area have been Philadelphia and New York, but a dispatcher for one company is scheduled for trial this year in connection with a Virginia crash that killed four people and injured 54. A bus overturned north of Richmond last year after the dispatcher allegedly ordered a driver who complained that he was tired to head back on the road.

The company that operated that bus, SkyExpress, reportedly had been cited for driver fatigue 46 times in the two previous years. It was ordered shut down after the fatal accident, but authorities said it resumed operation under two other names within days.

The federal action was described as the culmination of a year-long investigation of the companies. The announcement came seven months after a National Transportation Safety Board report that said curbside companies were five times more likely to be involved in fatal accidents than conventional intercity bus service companies.

In 2009, 221 people died and 10,000 were injured in bus crashes of all sorts.

The NTSB said the surge in intercity bus services since 2005 had overwhelmed state and federal inspectors: 2,327 safety inspectors were responsible for 53,097 buses.

“With these actions today, the DOT and its state partners are telling bus operators to put safety first or get put out of business,” said NTSB Chairman Deborah A.P. Hersman. “We’ve seen the tragic results of rogue operators too many times in our investigations.”

Hersman said NTSB investigators have “regularly identified bus operators that should not have been operating and who deliberately restructured their operations to skirt federal safety regulations.”

The crackdown was welcomed by the American Bus Association, whose membership includes many curbside companies that are in compliance with federal regulations.

“It’s good for all of the traveling public, because it means that people will not be riding these unsafe companies,” said Peter J. Pantuso, president of the bus association. “Certainly, here in the Washington area, whether people ride on BoltBus or Megabus, or NYC-to-DC or Vamoose, or any of the other carriers that are good, solid, legitimate operators, they know the difference between good companies and bad companies.”

Pantuso said that the illegal buses pulled up to curbside locations where passengers were known to congregate while awaiting legitimate curbside operators.

They also didn’t offer discounted seats. “They were charging the same as good companies,” he said.

The shutdown orders named three companies — Apex Bus, I-95 Coach and New Century Travel — that each operated a network of other bus companies. Among their 26 subsidiary companies were 13 that authorities said had ignored earlier shutdown orders. The companies were based in Georgia, Indiana, Maryland, New York, North Carolina and Pennsylvania.

“My guess is wherever you see these companies listed, nobody’s ever seen them in those markets,” Pantuso said. “These companies base themselves in safe havens like Pennsylvania and North Carolina, which may not have as vigilant of an inspection system. They’re based there just for registration, and they run in and out of New York City.”

Anne S. Ferro, administrator of the Federal Motor Carrier Safety Administration, said the targeted companies used unlicensed drivers who were not subjected to required drug and alcohol testing. They also were allowed to drive far more hours than federal rules allow.

“Our enforcement teams found multiple patterns of glaring safety violations by the three networks of enterprises,” Ferro said. “These enterprises have deliberately structured their operations to dodge federal safety laws. They also used buses that were mechanically unsafe and in disrepair.”

She said inspections revealed a pattern of bad or underinflated tires, worn brake pads and missing safety lights.

The carrier safety administration issued a rule Thursday expanding its ability to block bus companies from continuing their operations through affiliate companies when faced with a shutdown order.

LaHood and Ferro also said Senate legislation in a conference committee would give the agency vastly expanded enforcement capability and raise the penalty on companies that violate rules from $2,200 to $25,000 a day.