Jordan Larsson, who plays for Helsingborgs, was confronted on the pitch after his team lost 2-1 to Halmstads in a relegation play-off in November.
Henrik Larsson was Helsingborgs coach at this point and he and his son went across to the fans at full-time to thank them for their support and express their disappointment with the result. However, the pair were met by a hail of missiles from the stands before a group of the fans took to the pitch.
As a result twelve men have been fined up to £1,020 each after being found guilty of forcibly removing Larsson Jr's shirt.
In the aftermath of the incident Larsson Sr stepped down as manager, whilst Larsson Jr moved to top-flight side NEC Nijmegen the following January.
The incident led to calls from Interior Minister Anders Ygeman to improve the security at football stadiums in Sweden.