Two former executives of Mitsubishi Motors Corp. pleaded not guilty Thursday to falsifying reports on defective parts and thereby failing to prevent a fatal accident in Yokohama in 2002.

Hiroshi Murakawa, 58, who served as the head of Mitsubishi Motors' product quality department, and Hirotoshi Miki, 56, a former senior official of the section, said in the opening session of their Yokohama District Court trial that they could not foresee the accident, in which a defective hub caused a wheel to fly off a moving MMC truck and strike and kill Shiho Okamoto, 29, and injure her two children.

Murakawa and Miki were charged with negligence resulting in death and injury. In court, they said they were sorry for the victims but claimed they did not perceive that a component of the truck would be too fragile to hold the wheel, and therefore were not negligent.

A separate trial began Sept. 1 before another Yokohama court for the automaker and three former executives, including former Mitsubishi Fuso Truck & Bus Corp. Chairman Takashi Usami, 64, on charges that they falsified reports to the government in order to avoid vehicle recalls.