Iraqi security forces have detained 51 suspects following the car bombing in the Shi'ite holy city of Najaf.
The death toll in Najaf has risen from 48 to 52 and the number of injured from 90 to 145 in yesterday's explosion not far from a funeral procession near the Imam Ali mosque.
The bombing in Kerbala, which killed 14 people and injured 57, is believed to be related to the Najaf attack.
Four men, three of them believed to be foreigners, were killed in a roadside ambush not far from Samarra today.
And three Iraqis, including a woman, were killed in separate attacks north of the capital.
In Canada, international electoral experts are attending a closed-door conference in the capital, Ottawa, to discuss preparations for Iraq's elections next month.
A key issue under consideration will be the monitoring of the elections by international observers.
