Toyota Motor Corp chief Akio Toyoda stepped to center stage in a sprawling U.S. investigation of the Japanese automaker's safety crisis, apologizing to consumers and pledging reforms to skeptical lawmakers.

I am deeply sorry for any accidents that Toyota drivers have experienced, said Toyoda after being sworn in before the House Committee on Oversight and Government Reform.

His appearance marked a dramatic peak in a safety crisis that broke a month ago with a series of recalls over unintended acceleration and braking problems that now includes more than 8.5 million vehicles globally.

Dressed in a gray, pinstriped suit, Toyoda said he, more than anyone, wanted Toyota cars to be safe. My name is on every car, Toyoda said in English before using a translator to answer lawmakers' questions.

But he emphatically rejected a theory that some of the acceleration problems are in the electronics rather than the recalled sticky accelerator mechanisms and floor mats that can trap the accelerator pedal.

I'm absolutely confident that there is no problem with the electronic throttle system, Toyoda told the committee.

The unintended acceleration problems have been linked to at least five U.S. deaths, with 29 other fatality reports being examined by U.S. authorities.

Representative Paul Kanjorski, a Democrat from Pennsylvania, warned Toyoda that his company would have to pay for the deaths and injuries as U.S. lawsuits mount.

You will be called upon to pay compensation, Kanjorski said.

The oversight committee's chairman opened the hearing hours earlier by recounting a horrific crash that sparked the big recalls and blasting Toyota for boasting of saving $100 million by limiting a 2007 recall of floor mats implicated in the fatal accident.

The panel will hear from a relative of Mark Saylor, an off-duty California Highway Patrol officer who was killed last August, along with three members of his family, when the Toyota Lexus sedan he was driving sped out of control.

Toyota either ignored or minimized reports of sudden acceleration, said oversight panel chairman Edolphus Towns, a Democrat from New York.

U.S. Transportation Secretary Ray LaHood, who preceded Toyoda before the panel, labeled recalled Toyota vehicles as not safe.

Toyota, founded by Toyoda's grandfather, now faces a criminal investigation and a securities probe in the United States as well as unresolved questions about hundreds of incidents of unintended acceleration reported by consumers.

In his statement to the committee, Toyoda extended his condolences to the Saylor family and said he was deeply sorry that the company had allowed quality standards to slip during a period of fast growth over the past decade.

Toyota has promised internal reforms intended to increase attention to safety and ensure that future recalls happen more quickly in response to consumer complaints.

(Additional reporting by Kevin Krolicki and Kim Dixon in WASHINGTON; David Bailey in DETROIT; Graphic by Catherine Trevethan; Writing by Tim Dobbyn; Editing by Matthew Lewis)