Eight Liverpool and Manchester United fans have been arrested, including two on suspicion of tragedy chanting, after an FA Cup clash.
Police confirmed the men aged between 19 and 59 were arrested on suspicion of a range of offences including possession of drugs and pyrotechnics.
Two Manchester United fans were arrested on suspicion of tragedy chanting.
Greater Manchester Police said the incidents "will not be tolerated".
A ninth man, aged 34 from Edinburgh, was charged with possession of a class B drug, possession of a pyrotechnic and throwing missiles, and has since been bailed.