The US auto-safety regulator, National Highway Traffic Safety Administration (NHTSA), revealed on Friday that it had opened investigations into Bayerische Motoren Werke (BMW) and Mazda cars for probable defects that can result in the failure of power steering, increasing the risk of accidents due to loss of vehicle control.

The NHTSA investigations specifically pertains to 48,764 BMW Z4 sports cars sold from 2003 to 2005 model years; and 293,787 Mazda3 cars from 2007 to 2009.

According to the details forwarded by NHTSA, nearly 107 complaints have been received about the BMW Z4 model’s alleged loss of power-assisted steering and the subsequent need for excessive steering effort to maintain control; and 33 complaints have been received about a similar problem in the Mazda3 models.

The steering wheel failures typically occurred when vehicles were speeded beyond 45 miles per hour, at temperatures above 75 degrees F.

Though the NHTSA specified that there were no fatalities reported among the BMW Z4 and Mazda3 complaints, the agency added that one complaint involved a crash, and quite a few complaints reported loss of vehicle control or “near-miss incidents.”

While in both BMW Z4 and Mazda3 cases the NHTSA is still at the early stages of an official appraisal, the investigation process has been accelerated, following a massive safety crisis at Toyota Motor Corp, resulting in the global recall of over 10 million vehicles.