Crowds at the Allsvenskan football match, played April 25th on Syrianska's home arena, became aggressive following referee Martin Ströbergsson's decision to send off AIK's Teteh Bangura in the first half.
Violence erupted in the stands, and several objects were thrown onto the pitch, including a firecracker that struck assistant referee Daniel Wärnmark.
Strömbergsson finally decided to interrupt the match, only 20 minutes into the game.
Up until Thursday, it has been unclear which team has been to blame for the incident, but the Swedish Football Association has now decided that AIK must pay a 150,000 kronor fine.
As Syrianska was in the lead by 1-0 when the game was interrupted, the association has also awarded the football team points for a 3-0 victory.
Although the Swedish Football Association has reached their verdict, the Södertälje police force is however still investigating the events of April 25th, writes news agency TT.
"Several different things have happened, and we want the full picture before we decide who has done what,” Mikael Alfredsson of the Södertälje police told TT.
Shortly after the Football Association announced the verdict, AIK announced on its website it planned to appeal the decision, saying it "didn't share the opinion" of the association's disciplinary committee.