Nicholas Katzenbach, who held influential posts in the Kennedy and Johnson administrations and played a prominent role in federal desegregation efforts in the South, has died. He was 90.

A Princeton University spokesman confirms Katzenbach died Tuesday night at his home in Skillman. A cause of death was not disclosed.

Katzenbach was among the bright young legal minds brought into Robert Kennedy's Justice Department and he assisted in many prominent matters.

He wrote a legal brief in support of President John F. Kennedy's decision to blockade Cuba during the missile crisis and helped secure the release of prisoners captured during the Bay of Pigs raid on Cuba, in 1961.

Katzenbach was a Princeton graduate and had a long relationship with the Ivy League school.

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