An alleged white supremacist has been charged with targeting a black Charlottesville, Virginia, activist running for city council with violent, racist threats, authorities said Wednesday. Those threats led the activist, a deacon and co-founder of Charlottesville’s Black Lives Matter chapter, to drop his campaign, according to prosecutors.

Daniel McMahon, a 31-year-old resident of Brandon, Florida, was a known figure in hateful white supremacist circles on social media, according to the Associated Press. McMahon went by the alias “Jack Corbin” and wrote posts on the social media platform Gab that were shared by the Pittsburgh synagogue shooting suspect, the AP reported.

His alleged victim, who was named only with initials in the court filings, was identified by the Daily Progress as activist Don Gathers. Gathers, a deacon in a Baptist church and an activist for racial justice, had announced in January a plan to run for city council on a platform to help the city “heal” after the deadly “Unite the Right” white supremacist rally in Charlottesville in 2017. But the next day, when Gathers was scheduled to formally announce his campaign, he instead told a crowd of supporters that he had decided to delay his run for office, citing a doctor’s warning that he was still recovering from a heart attack the previous fall. That night, he also resigned from the Civilian Police Review Board, according to the Daily Progress.

It’s not clear what McMahon allegedly said to Gathers or how exactly he conveyed the threats, but according to the Washington Post, those alleged threats began on social media the night that local media reported his intention to run for office and continued a couple of days after Gathers halted his campaign.

“The alleged targeted and racially motivated actions by Daniel McMahon were an attempt to disrupt the American political process,” David W. Archey, special agent in charge of the FBI’s Richmond Division, said in a statement Wednesday.

According to an analysis from the Network Contagion Research Institute, the Pittsburgh synagogue shooting suspect, Robert Bowers, interacted with McMahon more than any other user on Gab before the October 2018 shooting. In addition to racist, anti-Semitic, and homophobic comments, McMahon encouraged violence against members of antifa and praised the neo-Nazi who killed protester Heather Heyer at the Unite the Right rally. McMahon also reportedly praised Bowers after the shooting.

McMahon has been charged with bias-motivated interference with a candidate for elective office, cyberstalking, and transmitting threats to injure in interstate commerce. Those last two charges carry up to five years in prison, according to the Justice Department.

McMahon’s lawyer told the AP that his client “categorically” denied all accusations.