The fighting appears to be the most intense to shake Tripoli this year. There were at least four people dead but it was not immediately clear if they were militiamen or civilians, an official said.
It is unclear how many of the dead were militiamen or civilians. The Red Crescent did not immediately respond to a request for comment. The escalation follows months of relative peace after nearly a decade of civil war in Libya, where two rival sets of authorities are locked in a political stalemate. Longstanding divisions have sparked several incidents of violence in Tripoli in recent years, although most have been over in a matter of hours.