Shamrock Rovers fans have been accused of going to Belfast “with the intent to engage in sectarian behaviour”.
Flares, seats and other missiles were thrown onto the pitch as trouble broke out during a football game at Windsor Park on Monday night.
Fans taunted each other with sectarian chanting during the first half of the match between Shamrock Rovers and Linfield and riot police were called in to deal with the disorder.
Flares, one orange and one green, were thrown onto the pitch but play continue.
Police released a statement on Tuesday saying a section of Shamrock Rovers fans had been involved in the disturbances.
“Police officers dealt with a disturbance in Windsor Park last night involving a section of Shamrock Rovers fans. A number of officers were injured while dealing with this disorder.
“Calm was restored within the grounds by police and at the end of the match officers ensured that all fans could leave safely.”
There was more trouble in Tates Avenue where, police said, a small crowd threw missiles at police.
No-one was injured and no arrests were made, although police said they are continuing to investigate.
SDLP Assembly member for south Belfast said the trouble followed scenes of violence at a match in Dublin last week, but reiterated that there is no excuse for what happened.
“It appears that some Shamrock Rovers fans came to Belfast with the intent to engage in sectarian behaviour. This is totally unacceptable and will be condemned by true football fans across the Island.
“Whilst tonight’s scenes follow violence by Linfield fans during the first leg in Dublin it remains unjustified and totally unjustifiable.
“Football has been dogged by sectarianism for decades. Events like tonight must resolve our determination to work together to eliminate sectarianism from football.
“It is a crime in Northern Ireland to engage in sectarian chanting or behaviour during a football game. I trust that the PSNI will be reviewing CCTV footage of fans tonight and take steps to prosecute where appropriate.”