© Reuters. A Ford logo is pictured at a store of the automaker, in Mexico City

By David Shepardson

WASHINGTON (Reuters) - Ford Motor (NYSE: ) Co on Monday warned an additional 33,000 owners of older pickup trucks in North America to stop driving them until potentially defective Takata Corp air bag inflators can be repaired.

In January, Ford told 2,900 owners of model year 2006 Ford Ranger trucks to stop driving immediately after a second death was linked to inflators built on the same day.

The expanded warning was prompted by additional testing, Ford, the second largest U.S. automaker, said in a statement, and now covers a broader time frame of production.

Mazda Motor Corp said it was issuing a similar expansion for about 1,800 2006 Mazda B-Series trucks that were built by Ford after it had issued a warning for 160 trucks in January.

The National Highway Traffic Safety Administration (NHTSA) said the vehicles pose "an immediate risk to safety" and urged owners to immediately schedule a free repair.

Ford and Mazda have replacement air bag inflators available now and will tow vehicles to a dealership for repairs as well as provide loaner vehicles free of charge, the companies and NHTSA said. About 90 percent of the vehicles subject to the "Do Not Drive" warning are in the United States.

Two U.S. senators in January questioned why Ford’s warning only applied to a small number of the 391,000 2004-2006 Ranger trucks recalled because of Takata air bags in 2016 in the United States.

Ford said last month the death in a July 2017 crash in West Virginia in a 2006 Ford Ranger was caused by a defective Takata inflator after a similar 2015 death in South Carolina.

At least 22 deaths worldwide are linked to the Takata inflators that can rupture and send deadly metal fragments into the driver’s body.

The faulty inflators have led to the largest automotive recall in history. The other 20 deaths have occurred in Honda Motor Co vehicles, most of which were in the United States.

About a quarter of the 2,900 vehicles have been repaired since Ford issued the warning last month, the company said on Monday.

Takata said in June it has recalled, or expected to recall, about 125 million vehicles worldwide by 2019, including more than 60 million in the United States. About 19 automakers worldwide are affected.

Takata inflators can explode with excessive force, unleashing metal shrapnel inside cars and trucks and have injured more than 200 people. The defect led Takata to file for bankruptcy protection in June.