The assassination of the Rev. Martin Luther King Jr. was remembered on Friday in the southeastern United States -- where he was born and preached and where he was shot dead 40 years ago. Mike Cooper reports from the slain civil rights leader's hometown of Atlanta, Georgia.

Bernice King and Martin Luther King III, two of the Rev. Martin Luther King Jr.'s children, began the day by laying a wreath at the crypt where their father and mother, Coretta Scott King, are buried.

Then, at Ebenezer Baptist Church, the inner-city Atlanta church where King preached, more than 2,000 high-school students recited a pledge to follow King's principles of non-violent social change.

Bernice King, who was five years old at the time of King's assassination, told the students she went through anger, rage and hatred as a teenager, but she now knows that non-violence is the only alternative today.

"I suggest to you that you make non-violence your personal way of life and recognize it is a daily fight. It is a daily quest. It is a discipline that starts with you. And as you are personally transformed, you will have the same power that Dr. King had to transform the issues and the problems and the conflicts that are presented in your generation," she said.

Also in Atlanta, the King National Historic Site opened a new exhibition in remembrance of King's assassination 40 years ago. It includes the wooden wagon, pulled by mules, that led King's 1968 funeral procession and a march by 200,000 people through Atlanta streets. In the state of Indiana, Barack Obama, who could become the first African-American to win a presidential nomination, remembered King's message during a town hall meeting.

"This is the struggle that brought back Dr. King to Memphis. It was a struggle for economic justice for the opportunity that should be available to people of all races and from all walks of life. Because Dr. King understood that the struggle for economic justice and the struggle for racial justice were really one that each was a part of a larger struggle for freedom for dignity and for humanity," he said.

In Memphis, Tennessee, where King was shot by James Earl Ray, presidential candidates Hillary Clinton and Senator John McCain delivered speeches.

Also in Memphis, about 1,000 people marched in the rain to remember King -- and the strike by sanitation workers that brought King to Memphis, where he was shot and killed on a downtown hotel balcony.