The president of Mitsubishi Materials has apologized for falsification of inspection data at 2 of its subsidiaries.

The latest disclosure comes after similar misconduct was uncovered at Kobe Steel, Nissan Motor and Subaru.

Company President Akira Takeuchi said the affected parts were shipped to hundreds of companies -- including car and aircraft makers.

Takeuchi said, "The Mitsubishi Materials group will work to improve its internal control system and further promote compliance. We want to prevent a recurrence, and regain the trust of the public."

Company officials say the misconduct occurred at Mitsubishi Cable Industries and Mitsubishi Shindoh.

Workers altered inspection data on the strength and size of rubber and copper products to meet client standards.

Officials say they may have been shipped to as many as 258 companies. Japan's defense minister says affected items were used in some defense equipment.

The subsidiaries were aware of the falsification in February, but kept shipping their products until October.

President Takeuchi said the delay in going public was needed to explain the situation to client firms.

The company says it will set up a panel to investigate the cause of the misconduct.