WASHINGTON (AP) — Car owners whose air bags have been replaced in the past three years may have had dangerous counterfeit bags installed, the Obama administration warned Wednesday.

Only 0.1 percent of the U.S. vehicle fleet is believed to be affected, the National Highway Traffic Safety Administration said in a statement. But industry officials briefed by the government said tens of thousands of car owners may be driving vehicles with counterfeit air bags. NHTSA testing has shown most of the counterfeit bags don't inflate or fail to inflate properly. In at least one case, a counterfeit bag fired shards of metal shrapnel on impact, the agency said.

NHTSA is asking car owners to check a government website, www.Safercar.gov, for information on how to contact a call center established by auto manufacturers to learn if their vehicle model is among those for which counterfeit air bags are known to have been made.

No deaths or injuries have been tied to the counterfeit bags, NHTSA said. But it's unclear whether police accident investigators would be able to identify a counterfeit bag from a genuine one, industry officials said.

NHTSA has compiled a list of dozens of vehicle makes and models for which counterfeit air bags may be available, but the agency cautioned that the full scope of the problem isn't clear yet and the list is expected to "evolve over time."

If a car is on the list and has had its air bags replaced during the past three years by a repair shop other than a new car dealership, NHTSA is asking owners to bring the vehicle into a dealership to be inspected at their own expense to determine whether the replaced air bags are counterfeit. Fees for checking out air bags could run $100 or more, industry officials said. Some types of cars have as many as eight air bags.

The counterfeit bags typically have been made to look like air bags made by automakers and usually include a manufacturer's logo. Government investigators believe many of the bags come from China, an industry official said.

The bags are marketed to auto body shops as the real deal, industry officials said. Auto dealerships that operate their own body shops are usually required by their franchise agreements to buy their parts, including air bags, directly from automakers and therefore are unlikely to have installed counterfeit bags, industry officials said.

But only 37 percent of auto dealers have their own body shops, according to information on the National Association of Automobile Dealers' website. Many consumers whose vehicles have been damaged are referred by their insurance companies to auto body shops that aren't affiliated with an automaker.

Consumers who bought replacement air bags online or who have purchased a used car that may have its airbags replaced in the past three years were also asked to check NHTSA's list.

Counterfeiting of a wide variety of auto parts has long been a well-known problem, industry officials said. But recent incidents have escalated concern by government officials. In August, federal agents confiscated nearly 1,600 counterfeit air bags and arrested a North Carolina auto mechanic, according to a report by the Charlotte Observer. The mechanic was tied by federal officials to another counterfeit air bag case last year in Tennessee, the report said.

Last February, Dai Zhensong, a Chinese citizen, pleaded guilty and was sentenced in federal court in Chattanooga, Tenn., to 37 months in prison for trafficking in counterfeit air bags, according to a statement made at the time by the U.S. Attorney's Office.

Zhensong was a part owner and manager of the international department of Guangzhou Auto Parts, which made a variety of auto parts, many of which were counterfeit, the statement said. In 2010, he traveled from China to Chattanooga to sell additional counterfeit air bags and other auto parts. The counterfeit air bags were manufactured by purchasing genuine auto air bags that were torn down and used to make molds to produce the counterfeit bags. Trademark emblems were purchased through Honda, Toyota, Audi, BMW and other dealerships located in China and affixed to the counterfeit air bags. The air bags were advertised on the Guangzhou Auto Parts website and sold for approximately $50 to $70 each, far below the value of an authentic air bag, the statement said.