Kenya's Wangari Maathai, the first African woman to win the Nobel Peace Prize, has died. She was 71.

The organization she founded, the Green Belt Movement, said in a statement that Maathai died Sunday at a Nairobi hospital after a long struggle with cancer.

The Nobel Committee awarded her the peace prize in 2004, citing her stand against Kenya's former oppressive government and work to encourage women to improve their lives.

Maathai started the Green Belt Movement in 1977 to help poor women in rural communities meet their basic needs for firewood, food and clean drinking water through a tree-planting program. The effort later grew to include focusing on issues of democracy, human rights, women's rights and peace.

The organization says it has mobilized hundreds of thousands of men and women to plant more than 47 million trees.

Maathai also served as a member of the Kenyan parliament, and as the country's deputy environment minister.

She attended college in the United States during the civil rights era in the 1960s, and said that experience inspired her to return home and do something positive for the people of Kenya.

Maathai was one of the founding members of the Nobel Women's Initiative, joining other female peace prize winners to support women's rights advocacy around the world.