Rival militias fought a gunbattle near office buildings and a five-star hotel in the centre of the Libyan capital on Wednesday, underscoring how volatile the country still is three months on from Muammar Gaddafi's death.
A Reuters reporter said exchanges of both heavy and light weapons could be heard coming from the Tripoli district of El-Saadi beach, a stretch of Mediterranean coast overlooked by office skyscrapers and the Marriott Hotel.
Ambulance sirens could be heard and plumes of smoke rose from the area of the fighting, which had been continuing for at least 40 minutes.
Interior Ministry forces had blocked a one kilometre section of road alongside the beach, but they did not appear to be intervening. Two militia pick-up trucks, with anti-aircraft guns on the back, drove past towards the fighting.
An Interior Ministry official said the fighting was between militiamen from the city of Misrata, and units from Zintan. Both groups fought to oust Gaddafi and now use their military power to underwrite a campaign for influence in the new Libya.
There are two groups fighting, said the official, Naji Awad, who was monitoring the battle from near the Marriott Hotel. Misrata controls a police academy building up the road and they are fighting with Zintan. We do not know why they are fighting, he said.
Libya's ruling National Transitional Council (NTC) is struggling to impose its authority on the country and form a functioning national police force and army.
Heavily-armed militias have stepped into the vacuum. They have carved the country into local fiefdoms and their fighters, though they express loyalty to the NTC, answer only to their own commanders.
Several militias from outside the capital have set up bases in Tripoli. They clash with each other intermittently often because of disputes over who controls which neighbourhoods of the city.
The violence on Wednesday was the first time in weeks that a major gunbattle had broken out right in the centre of the capital.
(Writing by Christian Lowe; Editing by Rosalind Russell)