Former Interior Secretary Stewart Udall, who sowed the seeds of the modern environmental movement as secretary during the 1960s, has died at his home in Santa Fe. He was 90.

His family says that after a fall last week, Udall was confined to his bed. The family says he had been in failing health and died Saturday of natural causes.

Under Udall's leadership from 1961 through 1968, the Interior Department aggressively promoted an expansion of public lands and helped win enactment of major environmental laws, including ones to protect endangered species.

He later became a crusader for victims of radiation exposure from the government's Cold War nuclear programs.

Udall is the father of Sen. Tom Udall, D-N.M., and uncle of Sen. Mark Udall, D-Colo.

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