Rival Libya militias in fresh clashes near Tripoli
Many died and hundreds were wounded in fighting following a protest against a militia on Friday
Fresh fighting has broken out between rival Libyan militias on the outskirts of the capital, Tripoli, after at least 43 people died in clashes on Friday.
The latest violence in the suburb of Tajoura pits local militiamen against incoming fighters from Misrata.
Friday's clashes occurred after protesters marched on the headquarters of the Misrata militia to demand that it leave Tripoli, and were fired upon.
The government is struggling to contain militias who control parts of Libya.'Very tense'
On Saturday Prime Minister Ali Zeidan confirmed that fresh fighting had been taking place in Tajoura.
He urged all sides to "exercise maximum restraint", adding: "No forces from outside Tripoli should attempt to enter the city because the situation is very tense and could escalate further."
AFP quoted Mr Zeidan as saying: "The coming hours and days will be decisive for the history of Libya and the success of the revolution."
Government-linked militias have set up checkpoints across the capital as security is tightened for the funerals of many of those killed on Friday.
Officials have updated the death toll from Friday's violence from 31 to 43. About 500 people were wounded.
Friday's fighting began after demonstrators marched on the headquarters of the Misrata brigades in the Ghargour district.
Misrata is about 200km (120 miles) to the east of the capital.
Mr Zeidan said the protest march had been "peaceful and came under fire when it entered Ghargour".
However, Libya's al-Ahrar television quoted Taher Basha Agha, the head of the Misrata militia at Ghargour, as saying that the protesters were armed.
"It was not a peaceful demonstration. They carried light arms and shot at us," he was quoted as saying.
Witnesses said the militiamen had initially fired to ward off the protesters, some of whom were children, but shot at the crowd when it continued to advance.
Other witnesses said armed men returned hours later to storm the militia HQ, with some buildings set on fire.
It is unclear how many casualties were caused at the initial protest and at the later fighting.
It is also unclear whether the attack on the Misrata militia HQ expelled the fighters there or whether they are still in place.
The militia was involved in clashes in the capital last week which left two people dead.
There have been increasing demands from civilians that the militias - which emerged during the 2011 revolution - disband or join the army, in line with an end-of-year deadline set by the interim government in Tripoli.
Some militiamen have been given salaries and taken into the government security forces but many still remain loyal to their own commanders.
Last month, Mr Zeidan was briefly seized by a militia group in Tripoli.
Two years after the overthrow of Col Muammar Gaddafi, Libya still has no constitution and divisions between secular and Islamist forces have paralysed parliament.