A white supremacist known for his extreme and harassing conduct online faces federal charges for alleged racially-motivated threats that prosecutors say sought to intimidate a black Charlottesville community activist who was considering running for office.

Daniel McMahon was arrested in Florida Wednesday. He has been charged with interference with candidate for elective office, bias-motivated interference with candidate for elective office, threats in interstate commerce and cyberstalking.

Both the indictment and superseding indictment that were unsealed Wednesday were extremely vague about the nature and content of McMahon’s allegedly threatening online communications.

The superseding indictment alleged that by “threat of force and violence,” McCahon “used the internet and his social media accounts to intimidate and interfere” with the prospective candidate’s campaign.

The indictment identifies McMahon’s alleged target as “D.G.,” an African-American Charlottesville resident who planned to announce his candidacy for city council at Jan. 8 event, but who instead announced at the event he would not be running.

That description fits Don Gathers, who co-founded Charlottesville’s Black Lives Matter chapter and who also has advocated for the renaming of Confederate monuments. At the time, Gathers’ decision to drop out of the city council race was described in local news reports as being related to health concerns.

Gathers did not respond to an email inquiry from TPM.

In a press release, the U.S. Attorney’s Office of Western District of Virginia alleged that the threats were “threats were made with the intent to injure and intimidate D.G., and were part of a course of conduct that caused D.G. to fear death and serious bodily injury.”

McMahon’s hate-filled online presence has been well documented by white supremacy watch dogs and even by a college newspaper, which claimed that its student journalists were harassed by McMahon’s online persona as he sought high-definition photographs of students protesting Confederate monuments.

According to Right Wing Watch, McMahon has used online monikers — including

Pale Horse,” “Dakota Stone,” and “Jack Corbin” — to promote fascism, deny the Holocaust and target activists who protest racism.

McMahon was in federal court in Tampa on Wednesday for a hearing on whether he should be released on bail. The hearing will continue on Monday, McMahon’s defense attorney, Nicholas Matassini Jr., told TPM. McMahon is being held at the Pinellas County Jail in the meantime.

According to Matassini, the government is seeking that McMahon remain in detention while he awaits trial. Matassini also said that firearms were found at McMahon’s home (where he lives with his parents). If the government points to the firearms as reason to hold McMahon in detention, his attorney said he will argue that the firearms were legally obtained and that they have no relationship to the charges that were brought against him.

A spokesperson for the U.S. Attorney’s Office in Western District of Virginia declined to comment.

Read the indictment below: