Gunmen killed three election candidates in Iraq on Thursday. Two campaign workers were also murdered in attacks two days before provincial elections are held.
The killings occurred in Baghdad, Mosul and the city of Baquba.
About 15 million people are expected to vote in 14 out of 18 provinces on Saturday. The poll is the first since 2005.
Sunni Arabs are expected to take part in large numbers after boycotting the previous elections.
Provincial councils are responsible for nominating governors who lead the administration, finance and reconstruction projects in their areas, controlling a combined budget of $US2.4 billion.
The vote will not include the three Kurdish provinces of Arbil, Dohuk and Sulaimaniyah, all in the north. Elections have been postponed in Kirkuk province.