(Reuters) — Ford Motor Co must recall 3 million vehicles with potentially defective driver-side Takata air bags, the U.S. auto safety regulator said on Tuesday, rejecting a bid by the second-largest U.S. automaker to avoid a recall.

The National Highway Traffic Safety Administration (NHTSA) said it was denying petitions filed by Ford and Mazda Motor Corp in 2017 seeking to avoid recalling vehicles with potentially dangerous inflators. The decision also will require Mazda to recall and repair driver air bags in approximately 5,800 vehicles. The recalls will cover various vehicles from the 2006 through 2012 model years.

The defect, which leads in rare instances to air bag inflators rupturing and sending potentially deadly metal fragments flying — especially after long-term exposure to high humidity – prompted the largest automotive recall in U.S. history of more than 67 million inflators. Worldwide, about 100 million inflators installed by 19 major automakers have been recalled.

The NHTSA said the “evidence makes clear that these inflators pose a significant safety risk.”

Earlier this month, the auto safety agency said at least 17 million vehicles with Takata air bags remain unrepaired.

Takata inflators have resulted in the deaths of at least 27 people worldwide and 18 in the United States, and over 400 reported injuries.

Ford said on Tuesday that the vehicles the NHTSA was ordering be recalled were subject to an earlier Takata recall for the passenger-side airbag, but did not comment further.

Mazda did not immediately comment.

The recall will apply to various Ford Ranger, Fusion, Edge, Lincoln Zephyr/MKZ, Mercury Milan and Lincoln MKX vehicles, along with Mazda 2007–2009 model year B-Series vehicles. The Mazda vehicles were designed by Ford, built on the same platform, and used the same air bag inflators as the Ranger trucks.

The regulator said Ford must within 30 days “submit to NHTSA a proposed schedule for the notification of vehicle owners and the launch of a remedy.”

Two people died in Takata air bag ruptures in previously recalled 2006 Ford Ranger vehicles with the most recent death in 2017.

In November, the NHTSA said it was rejecting a petition filed by General Motors Co to avoid the recall of 5.9 million U.S. vehicles with Takata air bags.

In November the agency said GM must recall the 2007-2014 model-year trucks and SUVs. GM estimated in securities filings that it would cost $1.2 billion if it were required to replace air bag inflators it had sought to avoid fixing and said it would recall 7 million vehicles worldwide.

(Reporting by David Shepardson; Editing by Richard Pullin and Leslie Adler)