Two security forces clashed in Tripoli late on Wednesday, killing one fighter and damaging property nearby, the Interior Ministry said on Thursday in a further sign of increasing tension between powerful factions in the Libyan capital.
A young man was also killed in a traffic collision as he fled the area along with other civilians, his friends told Reuters.
Two forces associated with the Presidential Council exchanged gunfire in a central part of Tripoli, ministry spokesman Abdel Monaem al-Arabi said, adding that an investigation into the cause of the incident had begun.
"I saw people running and cars rushing onto the opposite side of the road from fear," passerby Ali Errhoma, 31, told Reuters.
Much of Libya has for years been dominated by rival armed forces that control territory and vie for position while formally acting as paid elements of state security.
Tensions over a political standoff between the government that was installed last year through a UN-backed process and a rival administration appointed by the parliament have added to fears of an escalation.
A Reuters reporter said the area where the clashes took place was quiet on Thursday, with shop owners repairing damage to windows and normal life returning.