The man, who is an alleged member of a violent white supremacist group, flew back to the US from Ireland on Wednesday.
Gardaí have confirmed that an alleged neo-nazi spent almost a week in Ireland after he was refused entry into Germany. Last week, German media reported that a man known as Kyle M had been stopped by authorities when he was getting off a flight from Dublin to Berlin last Thursday.
The man was questioned by police at Tegel Airport before being put back on a plane to Dublin that evening. The 31-year-old is an alleged member of Atomwaffen, a violent far-right group. Members of Atomwaffen have been linked with five murders and a number of terror threats in the US.
It was reported that German police were tipped off by the FBI ahead of Kyle M's arrival. A spokeswoman for the FBI told JOE that it had no comment to make.
On Thursday, gardaí confirmed that the man had been in Ireland for a number of days and that he had returned to the US on Wednesday.
"An Garda Síochana are aware of a male US citizen who travelled from the US to Germany transiting Dublin and who was refused entry into Germany and returned to Dublin. This male has now returned to the US on 20/11/2019 from Dublin," it said in a statement.
The Department of Justice said it did not comment on individual cases.
