Five Britons were among several dozen people arrested during a demonstration by the right-wing English Defence League in Amsterdam.
Around 60 EDL activists turned up in the Dutch city on Saturday to support Dutch anti-Islam politician Geert Wilders.
The Britons were among 34 people arrested during the day, Amsterdam Police spokesman Rob van der Veen said. It is understood the five were held for not producing identification while on their way to the demonstration.
Officers equipped with horses and dogs were among those out in force as the protesters gathered in a specially designated area between the city centre and port.
Dutch authorities attempted to isolate the protest from anti-fascist groups and supporters of football team Ajax, both of whom urged their members to disrupt the afternoon demonstration.
Mr Wilders - who was barred from visiting Britain before being allowed to enter last year - has reportedly said he has no ties to the EDL and did not support the demonstration.
Writing in The Times last week, Jon Cruddas, Labour MP for Dagenham and Rainham, called on political parties to "choke off" what the EDL taps into.
He said the organisation was a small, violent street militia "but it speaks the language of a much larger, disenfranchised class".