Sen. Frank Lautenberg, D-N.J., died overnight of complications from viral pneumonia, his office said Monday.

At 89, Lautenberg was the oldest senator—andthe last World War II veteran serving in that legislative body. He enlisted at 18 and served in the Army Signal Corps in Europe during the war.

Lautenberg served on the Senate Committees on Appropriations; Commerce Science and Transportation; and Environment and Public Works. He had struggled with health problems earlier this year, and already had announced that he would not run for re-election in 2014.

Gov. Chris Christie, a Republican, can appoint someone to fill the vacancy, according to The Bergen Record, which was first to report the news. Christie will schedule a special election to find a permanent successor.

Lautenberg's career accomplishments included writing the law that banned smoking on airplanes, and he later helped craft legislation to ban smoking in all federal buildings. He also played a central role in raising the national drinking age to 21.

He wrote the law that prevents domestic abusers from owning firearms.

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