Daniel Inouye, Hawaii Senator, Medal of Honor-winner, has died at age 88

WASHINGTON (CNN) -- Daniel Inouye, the Medal of Honor-winning World War II veteran who represented Hawaii in the Senate for five decades, has died at age 88, his office announced Monday.

Inouye had been hospitalized for "respiratory complications" after starting treatment to regulate his oxygen intake last week, his spokesman, Peter Boylan, told CNN earlier Monday.

He won his ninth consecutive term in 2010 and was the second longest-serving senator in the chamber's history, trailing only Sen. Robert Byrd of West Virginia. He has been a senator for all but three of the Hawaii's 53 years as a state and had served as its first House member before that.

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