Bomb attacks in Kirkuk and Baghdad have killed at least 25 people and wounded dozens more.
A bomb at a market in the Baghdad Shia stronghold of Sadr City today killed at least 15 people and wounded 33.
Sadr City is the Baghdad stronghold of the Mehdi Army, a militia loyal to radical Shia cleric Moqtada al-Sadr.
Earlier, suicide bomber driving a truck packed with explosives killed 10 people and wounded 42 at a police station in central Kirkuk
Police and residents said several buildings had collapsed and victims were trapped under the rubble.
A police source said many buildings in the area bombed in Kirkuk suffered severe damage from the blast and rescuers were still searching for victims. One resident said he saw many casualties lying in the street and several buildings collapsed.
Just outside the borders of the largely autonomous Kurdistan region, Kirkuk's population is a volatile mix of Kurds, Turkmen and Sunni and Shia Arabs.
The attacks follow one of the bloodiest days in Iraq for months.
In all, at least 105 were killed in bombings and a shooting in the capital on a day when the United Nations said more than 34,000 Iraqi civilians died in violence last year. Four US soldiers were killed in a bomb attack in northern Iraq.