Election lead-up marred by violence

Also, two civilians were killed in clashes in the desert town of Qaim.

Police in the Shiite holy city of Najaf said they were making progress in catching those responsible for the bombing last week that killed 52 people.

Along with a bomb that killed 14 in nearby Kerbala, it was seen as an attempt to spark sectarian conflict in the run-up to the election.

Police chief Ghalib al-Jazairi said one man in detention had confessed to attending a guerrilla training camp in Syria.

Iraq accuses Syrian intelligence of aiding former Saddam loyalists and Islamist groups in Iraq.

Another man had been arrested who had filmed the scene before and after the bombing.