DETROIT -- The death of a Canadian driver has sparked a new investigation into a potentially deadly airbag problem affecting vehicles on both sides of the Canada-U.S. border.

Fatal airbag deployments in Canada are rare, but the July 8 fatality of a motorist in Newfoundland and Labrador marked the first time that a Canadian has been killed by an exploding airbag inflator, Transport Canada says.

The ruptured inflator on the 2009 Hyundai Elantra sent metal fragments into the passenger cabin, killing the driver in what officials described as a low-speed collision. The reason the airbag ruptured remains unknown.

Transport Canada and the RCMP are investigating the cause of the incident, as well as the manufacturer -- ARC Automotive Inc. of Knoxville, Tenn., which is already under investigation by American authorities. Transport Canada said ARC is co-operating with investigators.

Transport Canada said it is still determining what model vehicles may be affected by the new airbag problem. The agency's American counterpart is trying to determine the entire population of ARC inflators in the U.S., which it estimates at eight million in older vehicles made by General Motors, Fiat Chrysler, Hyundai and Kia.

Transport Canada says the safety benefits of airbags, which rely on controlled explosions that rapidly fill airbags in order to protect people in crashes, continue to outweigh the risks.

The death and investigations bring fresh urgency to a probe opened last year by the U.S. National Highway Traffic Safety Administration after an Ohio woman was injured by an ARC inflator. The U.S. safety agency on Thursday upgraded its investigation to an engineering analysis, a step closer to a recall.

In Canada, Transport Minister Marc Garneau could order a recall without having to wait for the company to do so.

"Any decision to recall is based on careful, verified information. At this point, the department's investigation -- which is still preliminary -- is needed to understand the issue," said Garneau spokeswoman Delphine Denis.

U.S. investigators began looking at ARC inflators in July of last year after getting reports that the Ohio woman was seriously hurt when her 2002 Chrysler Town & Country minivan crashed and the inflator ruptured. The agency said it also found another injury involving someone in a 2004 Kia Optima midsize car. In both cases, the inflators were made at ARC's factory in Knoxville, according to agency documents.

In the probe, the National Highway Traffic Safety Administration focused on inflators made from 2000 until September of 2004. The population includes about 2.6 million that were sold to General Motors.

According to NHTSA, the Elantra in the Newfoundland crash had an ARC inflator that was made in China, but it's unknown whether any of the same inflators were used in vehicles sold in the U.S. ARC has confirmed that the Canadian Elantra inflator "was substantially the same design" as the one used in at least one other U.S. model, the 2004 Kia Optima.

The administration said in a statement that it would direct the collection and testing of ARC inflators as it tries to determine what caused them to explode with too much force. The agency said it will focus on determining the entire population of ARC inflators in the U.S. and whether any inflators made in China were sold in the U.S.

Although the results are similar, the ARC problem is different from one that resulted in the recall of 69 million inflators in the U.S. made by Takata Corp.

Takata inflators have been blamed for at least 11 and as many as 14 deaths worldwide, as well as hundreds of injuries. Takata uses the explosive chemical ammonium nitrate to inflate airbags, but the chemical can degrade over time and burn too quickly, blowing apart metal inflator canisters.

Canada's colder -- and therefore less humid -- climate for most of the year largely minimizes the risk of the chemical degrading and heating too quickly, requiring it to be replaced.

ARC uses a small amount of ammonium nitrate to ignite another chemical that inflates airbags, and authorities say they are not looking at ammonium nitrate as the cause. They are looking into whether a manufacturing problem causes a vent to become blocked in the ARC inflators. With no place for the gas to escape, a metal inflator canister can be blown into pieces.

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With files from Jordan Press in Ottawa; AP's Rob Gillies in Toronto and Dee-Ann Durbin in Detroit contributed to this report.