(AP) — A civil rights activist who was the first African American woman to win a mayor’s race in Mississippi has died.

Unita Blackwell was 86. Her son, Jeremiah Blackwell Jr., said she died Monday in Ocean Springs Hospital.

Blackwell became active in the civil rights movement in the Mississippi Delta in 1964, when she and other black residents of Issaquena County tried to register to vote but were rejected because of a test rigged against them.

She was in the integrated Mississippi Freedom Democratic Party delegation that challenged the state’s all-white delegation at the 1964 Democratic National Convention.

From 1976 to 2001, Blackwell was mayor of Mayersville, a town of about 500. She received a MacArthur Fellowship genius grant in 1992 for her work on housing and water services.