Two rival militia groups clashed Wednesday in Tripoli, witnesses in the Libyan capital told dpa.
The clashes involved fighters originating from the Libyan towns of Misurata and Zintan and took place in Tripoli's coastal district of al-Saad.
"The road along the coast was closed as smoke rose from the area," one witness said.
There were no immediate reports about possible casualties or about the cause of the fighting.
The gunbattle is the latest in a series of armed conflicts among rival militias who joined forces last year in toppling the regime of the late leader Moamer Gaddafi.
Some of these militias continue to keep fighters in Tripoli, despite attempt by Libya's ruling National Transitional Council to re-establish security.