A longtime civil rights activist, the Rev. James Orange, died unexpectedly Saturday evening at Crawford Long Hospital in Atlanta, his eldest daughter said.

Orange, 65, went to the hospital for gallbladder surgery but passed away, said his daughter, Jamida Orange, 38. She said she did not know the cause of death.

A native of Birmingham, Orange had lived in Atlanta since the early 1960s, his daughter said.

He was involved in civil rights movements in Selma, Ala., Memphis, Chicago and other cities, organizing rallies and using his 6-foot-3 1/2 inch frame to help keep them peaceful.

In a July 1993 Atlanta Journal-Constitution article, civil rights leader Andrew Young described Orange as one of the "real soldiers of the movement ... a gentle giant."

Orange joined the civil rights movement in 1957 and was hired in 1965 by the Southern Christian Leadership Conference as a field staffer.

In 1995, Orange set up a committee that has organized an annual march and other activities honoring the Rev. Martin Luther King Jr. "That's his legacy," his daughter said.

He is survived by his wife, Cleophas Orange, and four children.