President Trump mentioned a far-right group during the first presidential debate, kicking off online celebrations by its supporters.
“Proud Boys – stand back and stand by,” he said, in a response to a question asking him to condemn white supremacist and militia groups. Members of the group online took the answer as a call to prepare for action.
Mr Trump then insisted that violence was coming from far-left activists: “Somebody’s got to do something about antifa and the left, because this is not a right-wing problem.”
Joe Biden, the Democratic challenger, answered back: “Antifa is an idea, not an organisation. That is what [President Trump’s] FBI director said.”