Mounted police have dispersed crowds of supporters ahead of a Champions League football match between Ajax and Manchester City in Amsterdam.
Images of the officers in riot gear carrying out charges were broadcast on Dutch television and posted on Twitter.
Amsterdam police phone lines were jammed for more than an hour and they could not be reached to confirm reports by state broadcaster NOS that seven men had been detained.
The area was calm again shortly afterwards.
Such incidents are not rare in Amsterdam.
Earlier this year there was a nearly identical scene, including mounted police, ahead of an Ajax-Manchester United match. In 2009 the same thing happened when the Netherlands' national team hosted England.