Thirty people in all were shot, some in the back, on Feb. 8, 1968 at South Carolina State University. It's the biggest blemish on South Carolina's mostly positive record of integration without violence and the first and one of the deadliest shootings during a protest on a college campus.
Hundreds gathered Thursday, including some of the wounded and former students on campus that day, at the gymnasium named for the three teens killed.
One speaker was the son of an organizer over a protest about a bowling alley still segregated in 1968. Bakari Sellers told the audience they needed to work to make sure America becomes a place that cares more about health care for young black pregnant women than about whether athletes stand for the national anthem.
"We remember because we cannot forget - because not enough has changed," Sellers said.
His father, Cleveland Sellers was the only person convicted in the incident. He was found guilty of inciting a riot and sentenced to a year in prison. He was pardoned 25 years later.
Nine white troopers eventually faced a federal trial and were acquitted. No state investigation was even conducted and the FBI decided not to re-open the case in 2007.
Highway Patrol Commander Christopher Williamson, the first African-American to ever hold that position, said he wishes he could forget troopers fired on unarmed people, but instead remembers that night to make South Carolina a better place.
"I will do everything within my power to make sure each of you will be treated fairly," Williamson said.
Thursday's ceremony also linked the shooting 50 years ago to the deaths of African-Americans at the hands of police today. One teen read a poem that started and ended with the line: "They see color. They fire. They plea. Then they walk away free."
The vice mayor of Charlottesville, Virginia, Wes Bellamy, saw blood shed last year in his city when white nationalists came to the city in violent protests. He said that clash shows fighting for civil rights still matters.
"Will you stand or will you cower? Will you stand and sacrifice, or will you sit and watch?" Bellamy asked. "These individuals we are celebrating today decided to give their lives for this fight."
A memorial honoring Henry Smith, Samuel Hammond Jr. and Delano Middleton sits near the hill where the troopers opened fire.
Sellers broke down as he said their names Thursday and recalled all the blood that was shed by the 30 people hit by buckshot, some in the back, as police opened fire.
"Fifty years ago was 16 years before I was born and it still hurts me like nothing I've ever known," Sellers said.
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