Acts of sabotage, mostly in the east of the country, prevented 101 polling stations from opening on Saturday in Libya's first post-Kadhafi election, the electoral commission's chairman said.
"Ninety-four percent of polling stations opened," Nuri al-Abbar told reporters in Tripoli, with voting underway in 1,453 out of 1,554 centres.
"Some of the polling stations were not opened. Because of security reasons, logistical materials haven't reached them," he said.
"We are currently dealing with this, sending material to the polling stations so they can start voting," stressed the commission chief.
The remarks came just five hours after the start of voting.
The commission, he said, was considering extending the deadline from 8:00 pm (1800 GMT) to midnight in voting centres affected.
Libya's elections for a General National Congress mark the first national poll after four decades of dictatorship under slain leader Moamer Kadhafi, who was toppled by a popular revolt last year.
"The turnout was excellent despite the high temperatures," Abbar said, noting that the preliminary figures of voter participation were being compiled.
He said the polling process for Libyans abroad was going "smoothly."
Most of the disruptions were concentrated in the east of the country, cradle of the 2011 uprising that overthrew Kadhafi and heartland of factions that have threatened to sabotage the landmark election.