TRIPOLI, Libya — The killing of an electoral worker and calls for a boycott on the eve of Libya’s first vote since the overthrow of longtime dictator Moammar Khadafy raised fears of election violence as campaigning came to an end Friday in a contest seen as a milestone on the country’s path toward democracy.
The Saturday election of a 200-member transitional Parliament caps a messy nine-month transition after a 2011 civil war that ended in October with the death of Khadafy, whose four-decade rule left the country deeply divided along regional, tribal, and ideological lines.
The Parliament will elect a transitional government to replace the one appointed by the National Transitional Council that led the rebel side during the eight-month war and held power in its aftermath.
Many in Libya’s oil-rich east feel slighted by the council-issued election laws, purportedly based on population, that allocate their region less than a third of the parliamentary seats, with the rest going to the western region that includes Tripoli and the sparsely-settled desert south.
In what it called an attempt to defuse east-west tensions, the council decreed on Thursday that the new Parliament will not be responsible for naming the panel that will draft a new constitution. Instead, the drafters will be directly elected by the public in a separate vote at a later date.
But this has not satisfied some in the east, who press for a boycott. ‘‘We don’t want Tripoli to rule all of Libya,’’ said Fadlallah Haroun, a former rebel commander in the east’s regional capital Benghazi.
On Friday, gunmen shot down a helicopter carrying polling materials near Benghazi, killing one election commission worker, said council spokesman Saleh Darhoub. He said the aircraft came under attack while flying over Benina airport on the city’s outskirts, and that the crew survived after a crash landing. It was not clear who was behind the attack.
The shooting was merely the latest unrest in the messy run-up to the vote. Late Thursday, former militiamen shut down three eastern oil refineries — in Ras Lanouf, Brega, and Sidr — to press the transitional government to cancel the vote, Haroun said. He said militiamen also have cut the country’s main coastal highway linking east to west.
Earlier this week, former rebel fighters and other angry protesters in Benghazi and in the nearby town of Ajdabiya attacked elections offices, setting fire to ballot papers and other voting materials.
Haroun said boycott supporters would take to the streets on election day to ‘‘prevent people from voting, because this is a vote that serves those who stole the revolution from us.’’
The vote also will be a test of the strength of Islamist parties, which have gained influence in Libya and other nations following the ouster of authoritarian regimes run by strongmen like Khadafy and Egypt’s Hosni Mubarak. Groups vying for power range from the politically savvy Muslim Brotherhood to the ultraconservative Salafis and former jihadists.
Late Thursday, supporters of the Justice and Construction party cofounded by the Muslim Brotherhood marched through the streets of Tripoli carrying the party’s flags.
The Alliance of National Forces, led by secular-leaning former premier Mahmoud Jibril, paraded in cars plastered with party posters. The National Front, which descends from a Khadafy-era opposition movement, lit the sky over the capital with fireworks.
A day earlier, the former rebel commander and former jihadist Abdel-Hakim Belhaj, who cofounded the Homeland, or Al-Watan party, spoke to hundreds of supporters in the heart of Tripoli, endorsing democracy that will serve Islamic Sharia law.
Those four parties are seen as front-runners in a highly unpredictable race.
