TRIPOLI, Libya – Fears of militia violence and calls for a boycott threatened Friday to mar Libya’s first nationwide parliamentary election, a milestone on the North African nation’s rocky path toward democracy after the ouster of dictator Moammar Gadhafi.

Today’s vote for a 200-member transitional parliament caps a tumultuous transition toward democracy after a civil war that ended with the capture and killing of Gadhafi in October.

Many Libyans had hoped the nation of 6 million would quickly thrive and become a magnet for investment, but the country has suffered a virtual collapse in authority that has left formidable challenges. Armed militias still operate independently, and deepening regional and tribal divisions erupt into violence with alarming frequency.

On the eve of today’s vote, gunmen shot down a helicopter carrying polling materials near the eastern city of Benghazi, the birthplace of the revolution, killing one election worker, said Saleh Darhoub, a spokesman for the ruling National Transitional Council. The crew survived after a crash landing.

Prime Minister Abdurrahim el-Keib vowed the government would ensure a safe vote today, and condemned the election worker’s killing.

“Any action aimed at hindering the election process is against the supreme interest of the nation and serves only the remnants of the old regime,” he said next to a screen showing the face of the slain worker. “It is threatening to the future of the revolution and its accomplishments … and an attempt to stop democracy for which Libyans sacrificed their souls.”

It was not immediately clear who was behind Friday’s shooting, but it was the latest unrest in a messy run-up to the vote that has put a spotlight on some of the major fault lines in the country — the east-west divide, the Islamist versus secularist political struggle.

Many in Libya’s oil-rich east feel slighted by the election laws issued by the National Transitional Council, the body that led the rebel cause during the civil war.