Tunisians vote in parliamentary election

Tunisians are voting in an election seen as pivotal to establishing democracy in the cradle of the Arab Spring uprisings.

Tunisians are lining up to choose their first five-year parliament since the 2011 revolution. (AAP)

Tunisians are lining up to vote to choose their first five-year parliament since they overthrew their dictator in the 2011 revolution that kicked off the Arab Spring uprisings.

When polls opened at 7am, dozens of voters were already queuing outside one polling station in Marseille Street in central Tunis.

Tunisia has been hailed as a beacon of hope compared with other chaos-hit countries like Libya and Egypt where regimes were also toppled.

But its transition has been tested at times by militant attacks and social unrest.

On the eve of the polls, Prime Minister Mehdi Jomaa warned of possible jihadist attacks aimed at disrupting the country's first post-revolution parliamentary election.

"We know that this will be a target (for jihadist groups) because it is unique in the region. It brings hope," Jomaa said during an inspection of security forces east of Tunis.

"They know that the success of (this election) is a threat to them, not only in Tunisia but throughout the region."

On Friday, Tunisian police killed six suspected militants - five of whom were women - in a raid on a house in the outskirts of the capital.

A policeman was also killed in an earlier firefight with the suspects.

Up to 80,000 troops and police have been deployed in a bid to protect voters.

About 5.2 million Tunisians are eligible to vote in about 12,000 polling stations, according to government figures.

Around 13,000 contenders from nearly 90 political parties are vying for the 217 seats up for grabs.

The Islamist Ennahda (Renaissance) and the secular Nidaa Tounes (Tunisia's Call) are thought to be the two front-runner parties.

However, there are concerns about low voter turnout.

Election officials have until Friday to announce the results.

Tunisia is to hold a presidential vote on November 23.

The parliamentary and presidential elections are intended to complete the process of democratisation in Tunisia.

The country's 2011 uprising ousted veteran autocrat Zine Abidine Ben Ali and ushered in a coalition government and interim president that won praise from the international community.

Several parties competing for seats in parliament are fronted by former regime officials.