Turnout for the provincial vote was about 51 percent, according to officials from Iraq's Independent High Electoral Commission. An estimated 13.8 million Iraqis were eligible to vote for more than 8,000 candidates, with 378 seats being contested.

IHEC board member Gaata al-Zobaie said ballot boxes and tallies from polling stations were being sent to Baghdad, and they would be entered in computers to tabulate the results.

After casting his ballot at the Rasheed Hotel in Baghdad, Prime Minister Nuri al-Maliki said every Iraqi who votes "tells the enemies of the political process that we are not going back".

Security was tight on Saturday, with voters searched before entering polling stations and numerous new checkpoints set up by soldiers and police in Baghdad.

For most of the day, only approved vehicles were allowed on the streets, which were largely deserted except for security forces and groups of children who took the opportunity to play football.

Despite heightened security in Baghdad and elsewhere, militants were still able to carry out attacks, killing 20 people.