The leader of a white supremacist group based in California has been arrested and charged with inciting riots.
Robert Rundo, co-founder of the Rise Above Movement, was arrested at LA International Airport on Sunday.
Three others have also been charged, one of whom remains at large.
The four are accused of travelling to events across California and to one in Charlottesville, Virginia, last year that led to the death of a woman and shocked the nation.
Earlier this month, four other members of the Rise Above Movement were charged with attacking counter-protesters at the Unite the Right march in Charlottesville in August 2017.
A woman died after a man drove into a crowd of counter-protesters.
The New York Times says Mr Rundo, 28, had crossed into Mexico and was "brought back" to the United States to be arrested at LA airport.
Fellow Rise Above Movement members Robert Boman, 25, and Tyler Laube, 22, were arrested on Wednesday while Aaron Eason, 38, remains at large.
The US Attorney's Office alleges they acted with "intent to incite, organise, promote, encourage, participate in, or carry on riots".
Three of the four, including Mr Rundo, are accused of attacking counter-protesters and journalists at a Make America Great Again rally in Huntington Beach, California, in March.
Mr Rundo is alleged to have assaulted two protesters, while Mr Laube allegedly punched a journalist in the face.
Mr Rundo travelled to Europe earlier this year with two of those already charged in the Charlottesville case to celebrate the birthday of Adolf Hitler.