Boston Free Speech Rally poster on Facebook. —Facebook

Three headliners scheduled to speak at a far-right rally in Boston on Saturday backed out Monday, casting doubt on the event amid strong opposition by city officials worried about a repeat of the bloodshed in Charlottesville.

Augustus Invictus, an Orlando activist who took part in the Charlottesville rally, said organizers of Boston’s rally texted him on Monday and said it was necessary to cancel the event “from a PR standpoint,’’ after the violence in Virginia.

Invictus, who attracted support from white supremacists when he ran for the US Senate as a Libertarian in Florida in 2016, said organizers indicated they were also worried about statements he has made espousing support for a “second American civil war.’’