The Rev. Al Sharpton called Sunday for an investigation of the district attorney prosecuting a group of black teenagers on serious criminal charges stemming from a high school fight involving a white classmate.

In a telephone interview from New York, Sharpton also said he would join thousands of people in Jena on Sept. 20 — the day one of the teens is scheduled to be sentenced on an aggravated second-degree battery conviction. Mychal Bell faces up to 15 years in prison.

"After that, if we need to, we'll go to Baton Rouge and see the governor and the Legislature," Sharpton said.

Sharpton said he wants the state attorney general and judicial oversight agencies to investigate the actions of LaSalle Parish District Attorney Reed Walters.

A telephone message left at Walters' residence was not returned Sunday. He has previously said he cannot comment because of the pending cases.

The case drew protests after five of the six teens, dubbed the "Jena Six," were originally charged with attempted second-degree murder and conspiracy to commit murder, carrying sentences of up to 80 years in prison. The sixth was charged in juvenile court.

The beating victim, who is white, was treated for injuries at a hospital and released the same day, and a motive for the alleged Dec. 4 attack at Jena High School was never established.

The beating came amid tense race relations in Jena, a mostly white town of 3,000 in north-central Louisiana. After a black student sat under a tree on the school campus where white students traditionally congregated, three nooses were hung in the tree. Students accused of placing the nooses were suspended from school for a short period.

In Jena on Sunday, the Rev. Jesse Jackson urged residents to come together to demand equal justice.

"Why be fighting when we can turn to each other and find common ground?" Jackson said. "Jena is too small not to move together."