Libyans went to the polls to elect a panel to draft a new constitution in another step in the country’s political transition following the overthrow of Muammer Gaddafi.
After four hours of polling on Thursday, election organisers said that turnout for the vote had reached just 18 percent.
Just 1.1 million of 3.4 million eligible voters went to register compared to more than 2.7 million that marked Libya's first free election in July 2012 - and that only after several extensions to the deadline.
UN envoy Tarek Mitri urged Libyans to "make your voice heard and contribute to your new state's constitution".
"All of us are aware that in a transition, a second election may not motivate people and mobilise energies in the same way the first elections did," he said.
The new charter is to cover key issues such as Libya's system of government, the status of ethnic minorities and the role of Islamic sharia law.
Two of the most powerful militias threatened on Tuesday to dissolve the General National Congress (GNC) assembly which they accuse of paralysing the country by endless infighting.
But Libya plans to go ahead with elections to a new transitional authority rather than wait for the constitution to be finalised.
Voting amid violence
The interior ministry said it had deployed more than 40,000 police to secure the North African nation's 1,500 polling stations. The defence ministry said it had also deployed 11,000 troops.
Gunmen, however, were still able to kill the caretaker of a school in the eastern city of Derna that was to be used as a polling station, local NGO coordinator Abdelbasset Abu Dhahab told AFP.
Five polling stations that were damaged in overnight bomb attacks in the same city remained closed and arrangements were being made for voters to use other polling stations.
Gunmen had also forced the closure of a sixth polling station in the town, Abu Dhahab added.
Elsewhere, election commission head Nuri al-Abbar said voting material could not be delivered to 29 polling stations in the southern town of Murzuq because of a protest movement by the local Toubou community.
In principle, all of the 692 hopefuls in Thursday's poll were standing as individuals, as political parties were barred from fielding candidates.
The candidates include 73 women, and the assembly will have at least six seats reserved for women.
Houda Bouzid, a woman in her 30s, said: "I've come to vote for a candidate to push for women's rights in the new constitution."
Another six seats are reserved for members of Libya's three main ethnic minority groups - the Berbers, Toubous and Tuareg.
But the two Berber seats will remain vacant as the main Berber organisations called a boycott to protest the failure of the interim authorities to guarantee the community - which played a major role in the 2011 uprising - a bigger say in drawing up the new charter.
Since Gaddafi’s fall, former rebel brigades armed with heavy weapons looted from his arsenals have carved out fiefdoms across the sprawling country.
Prime Minister Ali Zeidan's government is still struggling to assert its authority over militias which helped topple Gaddafi but kept their weapons and have become major political players.
The persistent lawlessness was highlighted by the brief abduction of Zeidan by former rebel militia in the capital last October.