Bill Richardson, the former New Mexico governor and UN ambassador just nominated for a Nobel Peace Prize for his work to free political prisoners, has died at 75

• Bill Richardson, the former two-term New Mexico governor and veteran diplomat, has died at 75.
• Richardson served as ambassador to the UN and Energy Secretary under President Bill Clinton.
• Last month, he was nominated for a Nobel Peace Prize over his work to free political prisoners.

Bill Richardson, the former two-term New Mexico governor and US Ambassador to the United Nations who just last month was nominated for a Nobel Peace Prize for his work to free political prisoners, died on Friday in his sleep at his summer home in Massachusetts. He was 75.

The Richardson Center for Global Engagement confirmed the veteran diplomat's death.