The Takata Corporation said Monday that its defective air bags, already responsible for the recall of more than three million vehicles worldwide, were sold to two additional automakers, Subaru and Mitsubishi.

A report from Takata to the National Highway Traffic Safety Administration did not identify the models or the number of affected vehicles.

Spokesmen for the two auto companies said the issue was being investigated.

The problem is defective air bag inflators; Takata says the propellant inside the parts was not properly prepared and could produce too much pressure when ignited. That could cause the inflator’s metal case to rupture, sending metal fragments into the driver. On the passenger side, the fragments are more likely to be shot toward the windshield.

Early in June, Toyota, Honda, Nissan, Mazda, Ford, Chrysler and BMW said they were recalling more than three million vehicles worldwide because of the Takata air bag inflators.