Algerians are voting in parliamentary elections amid fears of renewed violence in the country.

About 18 million registered voters are eligible to cast ballots for 389 members of the lower house of parliament.

More than 12,000 candidates from some 25 political parties are running in the elections. But parties aligned with President Abdelaziz Bouteflika are likely to retain a majority.

Official results are expected Friday.

Authorities imposed tight security ahead of the vote.

Wednesday, one police officer was killed and two people were wounded in a bomb blast in the city of Constantine.

Algeria's main rebel group, the "al-Qaida Organization in the Islamic Maghreb," has urged voters to boycott the polls. In an audio recording broadcast by al-Jazeera television, the group called the election a farce.

Last month, the militant group claimed responsibility for suicide bombings that killed 33 people and wounded more than 200 others in the capital, Algiers.

These are third parliamentary elections in Algeria since the military canceled the 1992 vote, sparking an Islamist insurgency in the North African country.

Some information for this report was provided by Reuters.