Ala Yaakoubi and Ahmed Ben Ahmed were arrested during their concert Aug. 22 when police stormed the stage, Tunisia Live reported.
Police released the pair after questioning.
Ghazi Mrabet, a lawyer representing the two rappers, said his clients were not present at the sentencing and they received no official word from the court about the charges.
Both rappers were charged with assaulting an officer on duty, slander and attacking public morals, Mrabet said.
Mrabet said Yaakoubi and Ben Ahmed are on the run.
Yaakoubi was previously sentenced to two years in prison for charges related to his song "Cops are Dogs," but he was released after serving six weeks.
Civil society organizations and artists harshly criticized the sentence.
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