After a riot sparked by a contested penalty and a flurry of red cards left 19 police officers hospitalised, Etoile Sahel said on Sunday they were ready to go to court over their 3-2 defeat by bitter rivals Esperance.
Thirty-eight police officers were injured when they were pelted by smoke bombs, stones, chairs and pieces of metal at Thursday's Tunisian league match in Rades, on the outskirts of Tunis.
The local football authorities also suspended the match referee, Karim Khemiri, until the end of the season, citing serious mistakes.
Etoile said on their website they "suspect match fixing in the match against Esperance", and will be handing a dossier of information to government officials.
The penalty award came late in the second half with Etoile leading 2-1 and there were three red cards in the final 10 minutes.
Esperance will play their next three games behind closed doors after dangerous levels of smoke bombs and running battles on the terraces saw the match twice interrupted.
After this weekend's games Esperance lead the Tunisian league on 44 points with Etoile in third on 36.
The visitors have been ordered to pay compensation for damage caused to the stadium, a venue often used to stage national team matches.
Football in Tunisia is regularly plagued by violence especially when the country's top clubs clash.
In recent years, violence has escalated so much that sports minister Majdouline Cherni described the outbreaks as "stadium terrorism".
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