Kobe Steel continues to be at the center of the scandal

The criminal investigation ushers in a new round of scandal that began when Kobe Steel admitted last October to widespread product quality certification data fraud, causing disruptions in global supply chains. The company's shares fell 4.3 percent to 0349 GMT.

Kobe Steel, a Japanese company that supplies steel parts to car, aircraft and train manufacturers around the world, has acknowledged that it has supplied falsified specifications to more than 600 customers and acknowledged that data fraud has been going on for nearly five decades.

The incident was one of the country's biggest industrial scandals in recent memory, sparking revelations of crimes by other Japanese companies misleading the country's reputation for improving production.

In its defense, Kobe Steel stated that it sold products that met safety and other standards, but did not meet the contract specifications agreed with customers.