DETROIT (Reuters) - Two senators on Wednesday raised the possibility of a sixth fatality linked to Takata Corp (>> Takata Corporation) air bags, as they announced a news conference to introduce the sister of someone who died in an Arizona accident in 2003.

So far, five fatalities, in Virginia, Oklahoma, Florida, California and Malaysia, have been linked to faulty Takata air bag inflators.

Democratic Senators Edward Markey and Richard Blumenthal said in a statement the sister of the Arizona accident victim will be at the news conference, on Thursday in Washington.

A spokesman for Markey declined to provide details and Blumenthal's office could not immediately be reached for comment.

The press conference will take place ahead of a Senate hearing at which officials from Takata, Honda Motor Co Ltd (>> Honda Motor Co Ltd), Chrysler Group and the National Highway Traffic Safety Administration are scheduled to testify regarding recalls involving the Takata air bags.

All of the deaths linked to the faulty Takata air bags, which can potentially explode and spray metal shrapnel at occupants of the vehicle, occurred in Honda cars. A Honda a spokesman said the Japanese automaker was "not aware of an incident in 2003" involving an air bag-related fatality in one of its vehicles.

Takata U.S. spokesman Alby Berman said the company was not aware of this incident mentioned by the senators and was looking into it.

Officials at General Motors (>> General Motors Company), Ford Motor Co (>> Ford Motor Company), Chrysler , Toyota Motor (>> Toyota Motor Corp), Honda, Nissan Motor (>> Nissan Motor Co Ltd), Mitsubishi Motors (>> MITSUBISHI MOTORS CORPORATION), Mazda Motor (>> Mazda Motor Corp), Subaru (>> Fuji Heavy Industries Ltd.) and BMW (>> Bayerische Motoren Werke AG) all said they were unaware of any fatal accidents involving their vehicles in Arizona in 2003.

On Tuesday, NHTSA said it had told Takata and five automakers - Ford, Mazda, Honda, Chrysler and BMW - to expand nationwide a regional U.S. recall of vehicles with the potentially defective air bags.

The regional recall has involved 4.1 million cars in hot and humid areas, where the air bags may be prone to fail, including Florida, Alabama, Mississippi, Georgia, Louisiana and parts of Texas along the Gulf of Mexico.

Around 16 million cars with Takata air bags have been recalled worldwide over the past six years, with more than 10 million of those in the United States.

Safety advocate Clarence Ditlow, executive director of the Center for Auto Safety, also will attend the senators' press conference. He said Wednesday he had not been told details of the Arizona accident.

(Additional reporting by Bernie Woodall in Detroit and Eric Beech in Washington; Editing by Richard Chang and Steve Orlofsky)

By Ben Klayman