For the past year, federal regulators have been investigating shrapnel-shooting airbags, linked to at least eight deaths and hundreds of injuries. These devices, made by Takata, are used by 11 different automakers, but until this week, Volkswagen had not been part of the investigation.

Yesterday, the National Highway Traffic Safety Administration revealed it was investigating a June 2015 rupture of a  Takata airbag in a 2015 Volkswagen Tiguan in Missouri. NHTSA has issued special orders to both companies, seeking information related to the incident.

According to NHTSA’s order [PDF], Volkswagen notified regulators of the rupture of a Takata airbag inflator on July 15, more than a month after the incident took place.

A spokesperson for VW tells the Detroit News that the rupture occurred after the vehicle hit a deer. The driver did not file a police report and did not seek medical attention.

NHTSA says information from VW and Takata – who have until Aug. 24 to comply with the orders – could help identify a cause for the June incident, which doesn’t fit the previous pattern of airbag ruptures linked to Takata safety devices.

For the most part, the previous ruptures have often occurred in older vehicles and in areas of high humidity, such as Florida, Puerto Rico, U.S. Virgin Islands, Hawaii, Texas, Louisiana, Georgia, South Carolina, Alabama and Mississippi.

Among the information NHTSA is seeking from the automaker and Japanese parts supplier includes a list of all models that have airbags with ammonium nitrate, from any auto supplier

The agency also asked for police reports and records related to the rupture and information on whether other VW vehicles have suffered ruptures.

Mark Gillies, a VW spokesperson, tells the Detroit News that the automaker is working to investigate the June incident with Takata.

Gillies say he was unaware of how many of the automaker’s vehicles are equipped with Takata airbags and had “no comment” on why VW airbags are not part of the wider Takata recall.

The company Tweeted back in May that while it uses Takata airbags, “the parts on our VWs are not part of the current recall.”

For its part, Takata says it doesn’t believe the most recent incident is related to the wider 33.8 million vehicle recall for defective airbags.

“While we are still investigating the cause of this malfunction, we believe it is unrelated to the previous recalls, which the extensive data suggests were a result of aging and long-term exposure to heat and high humidity,” Jared Levy, Takata spokesperson says. “We are cooperating closely with NHTSA and the vehicle manufacturer.”

Recalls of vehicles with Takata-produced airbags began slowly in 2008, but gained traction over the last year, culminating in the recall of 33.8 million vehicles in May.

The company and a plethora of investigators from the National Highway Traffic Safety Administration, as well as the 10 automakers affected by the recall have yet to identify what causes Takata’s airbags to rupture so violently. Because of this, it’s unclear whether or not vehicles already repaired are actually safe.

In fact, company also plans to re-recall about 400,000 vehicles that have already been repaired.

Takata announced it would change its use of the often volatile chemical ammonium nitrate in its safety devices and replace its batwing driver inflators.

U.S. investigates VW for ruptured Takata air bag [The Detroit News]

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