TRIPOLI, March 1 (Xinhua) -- UN Support Mission in Libya (UNSMIL) on Thursday expressed concern about the violence in the southern city of Sabha, which killed and injured a number of civilians.

"UNSMIL is deeply concerned by the escalation of armed conflict in Sebha, where at least 6 civilians were killed and 9 injured," the Mission said.

"The hospital was hit repeatedly. Indiscriminate use of weapons in densely populated areas must be stopped," the Mission added.

The city of Sabha, some 800 km southwest of the capital Tripoli, has been witnessing days of violent tribal clashes, which killed and injured several civilians.

The city has witnessed unprecedented insecurity due to the rise in crimes and kidnappings by armed groups, as well as frequent tribal clashes.