In the North African nation's first known case of an all-woman jihadist group, two of the ringleaders were jailed for 25 years, while the other seven were handed sentences ranging between three and 14 years. One woman was acquitted.
The sentences were handed out by a court in the capital Tunis on Tuesday, but Tunisia's prosecution service has no spokesperson and has not responded to journalists for months.
The justice minister declined to give further information on the case.
The case dates back to 2016, when reports appeared on social media of an attempt to assassinate then-interior minister Hedi Majdoub during a visit to his parents -- something his office denied.
Private radio station Mosaique FM reported that one of the gang lived next door to Majdoub's parents, and was accused of passing along information about his visits.
Following its 2011 revolt, which overthrew dictator Zine El Abidine Ben Ali and sparked the Arab Spring uprisings, Tunisia experienced a series of jihadist attacks that killed dozens of people including numerous security personnel and foreign tourists.
The authorities say they have made major progress against jihadists in recent years.