(AP) -- ORANGEBURG, S.C. (AP) - Friends and family are returning to South Carolina State University to remember three men killed and 27 injured after being shot by police at the school during a civil rights protest.

Today marks the 43rd anniversary of the incident that became known as the Orangeburg Massacre.

On Feb. 8, 1968, state troopers and police opened fire on a group of students who were protesting a segregated bowling alley after a tense standoff. None of the officers were injured.

An FBI investigation led to charges against nine troopers involved in the shooting, but a jury of 10 whites and two blacks acquitted them, finding they acted in self-defense.

Federal agents refused to reopen the case in 2007.

(Copyright ©2011 by The Associated Press. All Rights Reserved.)