– The problem of exploding air bags could be widening beyond Japanese manufacturer Takata Corp.

U.S. safety regulators are investigating inflators made by ARC Automotive Inc. that went into about 420,000 older Fiat Chrysler Town and Country minivans and another 70,000 Kia Optima midsize sedans.

The probe, revealed in documents posted Tuesday by the National Highway Traffic Safety Administration (NHTSA), comes just weeks after Takata agreed to recall 33.8 million inflators in the United States in the largest automotive recall in U.S. history. At least eight people have been killed worldwide by flying shrapnel from Takata inflators, and more than 100 injured.

The safety agency said it received a complaint in December about a 2009 incident in a 2002 Chrysler minivan but determined it was an isolated case involving an ARC driver's side inflator. Then in June, Kia told the agency about a lawsuit involving a 2004 Optima in New Mexico with an ARC inflator, so NHTSA decided to open an investigation. The two cases are the only known incidents involving ARC inflators in vehicles made by either automaker.

The agency said one person was hurt in each of the crashes.

In the Chrysler case, a probable cause was identified, but investigators don't know the cause of the Kia rupture. If the investigation determines that the inflators are a hazard, NHTSA will seek a recall.

The investigation also will determine how many of the suspect ARC inflators are on the road.

Fiat Chrysler, Kia and Knoxville, Tenn.-based ARC said in statements that they are cooperating in the probe. ARC pointed to a 60-year record of serving customers "with products that meet the most stringent global safety standards." Fiat Chrysler said it no longer uses the inflators that are being investigated.

Associated Press