In 1955, Emmett Till’s brutalized body was pulled from the Tallahatchie River, near Glendora, Mississippi. His corpse was so badly disfigured that his great uncle was only able to identify Till by his signet ring.

Just days before, the 14-year-old African-American boy was dragged from his bed for allegedly whistling at a white woman. His kidnappers tortured and killed Till, and then tethered his neck to a heavy cotton-gin fan wrapped with barbed wire in an attempt to make his body disappear forever in the river’s murky depths.

Instead, his body was found by fishermen, and the photographs documenting Till’s battered corpse in Jet magazine became a galvanizing image of the Civil Rights Movement. Till’s murder remains a powerful symbol of America’s legacy of racial terror today, especially in light of recent vandalism perceived to silence that history. As Jessica Campisi and Brandon Griggs at CNN report, for the third time in a decade, a memorial sign marking the spot where Till’s body was recovered has been ruined.

Back in 2007, the Emmett Till Interpretive Center first erected a sign in memory of Till, a Chicago native, who had traveled to Money, Mississippi, in the summer of ’55 to pay a visit to his great uncle. During the trip, he entered a county market where he may have whistled at Carolyn Byrant, a white woman who owned the store with her husband Roy.

Roy and his half-brother J.W. Milam subsequently kidnapped Till from his great uncle’s home, driving him in a pickup truck to the banks of the river. At some point, they stripped Till naked, beat and tortured him, gouging out an eye and clipping an ear before shooting him in the head.

After Till’s mangled body was found in the river, his mother insisted that his body be returned to Chicago. There, she held an open-casket funeral using a glass-topped casket now on display at the Smithsonian’s National Museum of African American History and Culture so the world would be forced to witness what happened to her son. In the Chicago Tribune, historian Elliott J. Gorn explains that after Jet published pictures of the funeral, the images of Till’s corpse “gave grim determination to what has been called ‘The Emmett Till generation’ of the civil rights movement.” The story of Till’s death grew even more upsetting a month later, when, despite eyewitness testimony and the admission they kidnapped Till, Bryant and Milam were acquitted of the murder by an all-white jury following just an hour of deliberation.

In an effort to confront Till’s murder and its own past, county board members and activists founded the Emmett Till Memorial Commission, which first installed the memorial sign at the site where Till’s body was recovered in 2007. But the year after it was erected, the marker was stolen and never found. A replacement sign was then riddled with dozens of bullet holes in 2016; that sign is now housed inside the Emmet Till Interpretive Center, a museum opened in 2015 dedicated to Till’s story and equal justice in the town of Sumner. The most recent marker was put up this July. Just 35 days after its installation, a local university professor reported it had been defaced with four bullet holes. Since the sign is located two miles down a remote gravel road, it’s unlikely the bullets came from someone randomly shooting signs. Instead, the incident appears to have been an intentional act. “Whether it was racially motivated or just pure ignorance, it’s still unacceptable,” Patrick Weems, co-founder of the Interpretive Center, tells CNN.

In a separate interview with Alex Horton of the Washington Post, Weems says that the issues of white supremacy and racial terror that motivated Till’s death are still at play in the U.S., and the violence toward the sign shows the struggle for equality and justice are far from over. “We didn’t deal with the root reasons in 1955. And we’re still having to deal with that,” he says.

According to its website, the Interpretive Center is rethinking how it can protect any future markers from being vandalized. The organization is currently looking to raise $100,000 to buy the property where the sign stands by the river and create a park and memorial site equipped with gates and security cameras. The Interpretive Center is additionally working on creating a website and app that can lead visitors to significant sites linked to the murder, like the spot where Till was kidnapped from, the court house where the trial took place and the location of the general store. The National Park Service is also looking into acquiring some of the sites associated with Till for a Civil Rights park in the Mississippi Delta.

Dave Tell, the author of the forthcoming book Remembering Emmett Till, tells Horton that he, for one, would prefer that the Interpretive Center leave the bullet-ridden sign up. “Replacing it means erasing the material evidence of the way the story still grips us,” he says.