BAGHDAD -- In what appeared to be a new phase in an intensifying conflict that has raised fears of greater bloodshed and a wider sectarian war, Iraqi soldiers opened fire from helicopters on Sunni gunmen hiding in a northern village Wednesday, officials said.
The air attacks were among clashes throughout the country between forces of the Shiite-dominated Iraqi government and Sunni gunmen that left at least 27 people dead and dozens wounded. The Sunni tribesmen were continuing a fight that began on Tuesday after the Iraqi army stormed a Sunni protest encampment in the village of Hawija, leaving dozens dead and injured.
Several others were killed Wednesday in explosions, including the detonation of a car bomb at a public market in the evening in a Shiite neighborhood north of Baghdad and a roadside bomb attack on an army patrol in Tikrit, also in the north.
The deadliest battles occurred near Hawija and Sulaiman Pek, northern towns near Kirkuk, and battles were still raging in the early evening.
In Hawija, the army shut off electricity, and troops shouted through loudspeakers, urging civilians to evacuate, witnesses said. Government helicopters also fired at Sunni gunmen on the ground in Sulaiman Pek.
The Sunni uprising, having now turned violent, represents a significant challenge to the rule of Prime Minister Nouri al-Maliki, whose consolidation of power over the security forces and the judiciary, and his targeting of high-level Sunni leaders for arrest, has raised alarms among world powers.
Mr. Maliki has presided over an unwieldy power-sharing government, which nominally gives prominent roles to Sunnis but in reality has resulted in political stasis, and he has signaled in recent months that he would prefer to move to a majority government, dominated almost solely by Shiites.
On Tuesday, two Sunni ministers quit to protest the raid in Hawija, and the largest bloc of Sunni lawmakers suspended participation in Parliament.
Mr. Maliki made no public comments on the situation Wednesday, but on Tuesday, after being pressed by U.S. officials and the United Nations, he said he would open an investigation into the events in Hawija, and promised to hold military officers accountable for any mistakes.
The deteriorating situation in Iraq highlights the sectarian tensions that have risen across the region, particularly amid the raging civil war in Syria. There, a largely Sunni rebellion is seeking to topple the government of Bashar Assad, which is dominated by Alawites, who belong to a branch of Shiite Islam.
In Iraq, the central government has aligned with the Syrian government and its greatest ally, Iran, while Sunnis here have sided with the rebels, and they now appear to be emboldened by the events in Syria to challenge their own government.
The clashes on Tuesday in Hawija killed nearly 50, mostly civilians, and injured more than 100, according to a final tally released Wednesday by Kirkuk's health department. Many of the wounded were transferred to cities in Iraq's semiautonomous Kurdish region in the north, where the quality of medical facilities is better.
Emma Sky, a key civilian policy adviser for Army Gen. Ray Odierno when he was the top U.S. military commander in Iraq, said the events in Hawija exacerbate concerns that the conflicts in Syria and Iraq are merging.
Associated Press contributed.