TOKYO (AP) — The CEO of Takata Corp., the Japanese air bag maker at the center of a defect scandal that has resulted in recalls of 33.8 million vehicles, appeared at a news conference Thursday for the first time since the problems emerged and apologized to shareholders.

Japanese seat belt and air-bag maker Takata Corp. Chairman and CEO Shigehisa Takada bows during a press conference regarding the expanding recall of his company's air bags, in Tokyo (AP Photo/Shuji Kajiyama)

Shigehisa Takada bowed along with two other senior company executives. He left the technical details of the briefing to other company officials but responded to numerous questions, apologizing for not appearing sooner.

"We are a company that should be providing safety. Our product quality should be assured," he said. "There are many things needing improvement. We must reconsider how to do that and also how to better manage our supply chain."

At least eight people have been killed and 100 injured by the air bags, which can explode with excessive force, spewing shrapnel into the vehicle. The problem has persisted for over a decade, affecting 11 automakers including Honda, BMW and Toyota.

Takada repeatedly expressed regret over the problems, saying their cause was still under investigation.

"Unfortunately, we still cannot tell you the exact reason," he said.

A chemical inside the air bags' inflators can kick in with too much force, blowing apart the metal inflator and sending shards flying. Exposure to moisture for extended periods appears to trigger the problem.

Takata's air bags have been installed in more than 50 million vehicles worldwide. The company says it has changed its air bag design and is no longer using the batwing-shaped inflator that was involved in the eight fatal accidents and most of the injuries.

The Japanese company faces a huge financial burden in responding to the crisis, but said its banks have been supportive.

Takada refused comment on the total cost of the quality problems.

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