The victims were among 132 protesters killed nationwide in the weeks leading up to Ben Ali's overthrow on 14 January 2011.
The mixed panel of military and civilian judges pronounced Ben Ali guilty of complicity in murder and attempted murder.
A separate case still being heard in Tunis concerns demonstrators killed in the capital and elsewhere.
Earlier in the day, a military court for the Tunis area sentenced Ben Ali to 20 years in prison in a case concerning the deaths of four men in the coastal town of Ouardanine, south of the capital, on 15 January 2011.
A civilian court sentenced Ben Ali to a total of 66 years in June last year on charges ranging from embezzlement to drug trafficking in a trial perceived by many Tunisians to be little more than a hasty show trial. The former first lady wife, Leila Trabelsi, who fled with her husband to Saudi Arabia, received 35 years for unlawful possession of money and jewellery.
Darul Ihsan Media Desk