Explosions across Iraq left at least 29 people dead Saturday after a massacre at a Sunni Muslim mosque a day earlier prompted fear of deepening sectarian violence.
Three car bombs detonated in the northern Iraqi city of Kirkuk, killing 21 people and wounding 130, Kurdish officials said.
Two of the dead were members of the security forces and the rest were civilians, said Farhad Hama Ali, a Kurdish security official in Kirkuk.
The oil-rich city has been under the control of Kurdish forces since June, when the Shiite-dominated Iraqi army abandoned it amid an offensive by Sunni Muslim militants. The retreat allowed Kurdish forces to move in and control the city, over Baghdad's objections.
Kurdish Iraqi soldiers known as peshmerga have been leading the fight against Islamic State, the Sunni extremist group that has taken over large swaths of northern and western Iraq. Backed by U.S. airstrikes, Kurdish forces dislodged the militants from the strategic Mosul dam last week and have engaged in clashes with the militants in other northern towns.
The U.S. military continued its airstrikes near the dam on Saturday, hitting an Islamic State vehicle, the U.S. Central Command reported in a statement. Since Aug. 8, the command has conducted 94 airstrikes across Iraq, 61 near the dam, the statement said.
In Baghdad on Saturday, a suicide bomber drove an explosives-packed vehicle into the entrance of an Iraqi intelligence headquarters in the central Karada district, leaving at least eight people dead, Iraqi news media reported.
In the normally placid northern city of Irbil, the capital of the semiautonomous Kurdish region, a bomb attached to a vehicle went off on a busy road. Four people were wounded in the blast near the offices of a Kurdish political party, according to the Kurdish news site Rudaw.
It was not immediately clear whether the explosions were related, but they came a day after the mass killing of Sunni Muslim worshipers primed anticipation of retaliatory strikes. Suicide bombings are a hallmark of Sunni militants.
Seventy-three Sunnis were reported killed Friday in Diyala province, east of Baghdad, when Shiite Muslim gunmen stormed a mosque and opened fire, residents said.
Also on Saturday, the head of the United Nations mission in Iraq urged the government in Baghdad to come to the aid of a northern city that has been surrounded by Islamic State militants and almost entirely cut off from food and water for nearly two months.
"The situation of the people in Amerli is desperate and demands immediate action to prevent the possible massacre of its citizens," the envoy, Nickolay Mladenov, said in a statement.
Mladenov's appeal came a day after Iraq's most influential cleric, the Shiite Grand Ayatollah Ali Sistani, called on Iraqi officials to airlift food and emergency supplies to the town of 18,000 people, mainly ethnic Turkmens who are adherents of Shiite Islam.
The siege of Amerli, about 100 miles north of Baghdad, has drawn comparisons with the plight of Yazidis, a small religious minority who were besieged by the Sunni extremists until U.S. airstrikes this month helped allow many to flee to safety.
The Islamic State's rapid rise has rekindled dark memories of the bloody sectarian strife that enveloped Iraq in the last decade. The Obama administration launched airstrikes to protect ethnic minorities and U.S. personnel in northern Iraq and is reported to be weighing further military action after the group released a video last week showing one of its fighters beheading American journalist James Foley and threatening the life of a second kidnapped American journalist.
Iraqi political leaders in Baghdad were locked in talks Saturday over forming a new government, which U.S. officials hope will forge a united front against the extremists. But the leaders of three major Sunni political blocs have suspended participation in the negotiations in protest of the Diyala mosque attack.