The Sabha Medical Center said in a statement it received one dead and two wounded people, after receiving 11 injured people two days ago, including women and children.
A military source said that "the clashes renewed after militants of Tabu tribe fired indiscriminate shells on our headquarters, forcing us to fire back."
The source stressed that after the exchange of fire from both sides, the city is currently witnessing cautious calm with gunfire heard from time to time.
Sabha has been witnessing heavy clashes between rival tribes since February, which so far killed 10 people and injured more than 30 others, according to a medical report.
The clashes also displaced more than 200 families from their homes.
The United Nations Support Mission in Libya expressed concern on several occasions about the military escalation in Sabha, demanding to stop indiscriminate use of weapons in densely populated areas.
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