Japanese automaker Suzuki is apologizing for improper road tests on some of its models but denies it illegally falsified mileage numbers.

Suzuki Motor Corp. shares fell in Tokyo trading Wednesday on Japanese media reports the company might have cheated on mileage.

Earlier this month, Mitsubishi Motors Corp. said it had systematically falsified mileage on several models to inflate them.

Nissan Motor Co. then bought a 34 percent stake in Mitsubishi for 237 billion yen ($2.2 billion), which Nissan Chief Carlos Ghosn called a deal because Mitsubishi stock had plunged more than 40 percent after the scandal broke.

Suzuki, whose lineup focuses on minicars, or models with small engines that make them eligible for tax breaks in Japan, said the dubious tests did not affect models sold abroad.