Three white fraternity brothers at the University of Mississippi are the subject of a Justice Department civil rights investigation after one of the students posted a picture of the trio posing with guns in front a bullet-riddled roadside memorial to Emmett Till, a black teenager whose 1955 torture and murder galvanized the civil rights movement. The picture was posted on one of the students’ private Instagram account in March, prompting a bias complaint to be filed with the university shortly after. The image was later deleted—after receiving 274 likes—when reporters began following up on it but resurfaced this week in a report by the Mississippi Center for Investigative Reporting. The report identified two of the students in the photo as Ben LeClere and John Lowe but did not identify the third. “LeClere posted the picture on Lowe’s birthday on March 1 with the message ‘one of Memphis’s finest and the worst influence I’ve ever met,’” according to the center’s reporting.

The students, one of whom was holding a shotgun and another an AR-15 semi-automatic rifle in front of the roadside plaque at the spot on the Tallahatchie River where Till’s body was found, were suspended by the Ole Miss chapter of the Kappa Alpha fraternity, a frat that regards Confederate Civil War Gen. Robert E. Lee as its “spiritual founder.” It is not clear whether the bullet holes in the memorial were from the students. A spokesperson for Ole Miss said the students were not disciplined in response to the bias complaint because the incident occurred off campus and, despite being offensive, was not a violation of the school’s code of conduct. The university said it notified local police about the image, which in turn informed the FBI. The university said the FBI said it would not investigate the incident further because it did not constitute a specific threat.

The U.S. attorney for the Northern District of Mississippi, however, said the image had been referred to the Justice Department’s Civil Rights Division for further investigation.