Iraq's most feared terror group claimed responsibility for slaughtering members of the Iraqi security forces in Mosul, where dozens of bodies have been found. The claim raises fears the terror group has expanded to the north after the loss of its purported base in Fallujah.
Meanwhile, insurgents attacked US and Iraqi targets on Sunday in Baghdad and in Sunni Arab areas.
Deputy Prime Minister Barham Saleh said sticking to the Jan. 30 election timetable would be a challenge, but delaying it would bolster the insurgents' cause.
Two US soldiers were injured in a Baghdad attack, and another died in a traffic accident north of the capital, the military said.
US and Iraqi forces killed 17 suspected insurgents in raids south of the capital on Sunday, Iraqi police said. Operations there included a dawn speedboat assault by US Marines and British and Iraqi troops on suspected insurgent hideouts along the Euphrates River, British media reported.
The speedboat assault included Marines, Britain's Black Watch regiment and Iraqi commandos and was directed at an area from which insurgents have been rocketing a British base, British media reports said.
A statement posted on an Islamist Web site in the name of al-Qaeda in Iraq, led by Jordanian terror mastermind Abu Musab al-Zarqawi, claimed responsibility for killing 17 members of Iraq's security forces and a Kurdish militiaman in Mosul, where insurgents rose up this month in support of guerrillas facing a US-led assault in Fallujah.
The claim could not be independently verified but the style of writing appeared similar to other statements by al-Zarqawi's group, which is responsible for numerous car bombings and beheadings of foreign hostages in Iraq.
The US has offered a US$25 million reward for al-Zarqawi's capture -- the same amount it is offering for Osama bin Laden.
At least 50 people have been killed in Mosul in the past 10 days. Most of the victims are believed to have been supporters of Iraq's interim government or members of its fledgling security forces.
Separately, al-Zarqawi's group claimed it detonated a car bomb near a US military convoy in the Hamam al-Alil area, near Mosul. It said the blast destroyed an armored vehicle and damaged another.
Although the claims were not verifiable, they raised fears that al-Zarqawi's organization had spread to Mosul, Iraq's third-largest city, 360km north of Baghdad. At least 43 suspected insurgents have been arrested as part of an ongoing operation to re-establish control of Mosul, a military statement said.
Al-Zarqawi's group, formerly known as Tawhid and Jihad, was believed to have been headquartered in Fallujah, the Sunni Arab insurgent bastion 65km west of Baghdad, before US and Iraqi forces overran the city this month.
Al-Zarqawi and the city's two major Iraqi insurgent leaders, Sheik Abdullah al-Janabi and Omar Hadid, apparently escaped the onslaught and remain at large. Before the assault, US intelligence officers speculated that al-Zarqawi would try to relocate to Mosul if he lost his base in Fallujah.
US and Iraqi officials launched the offensive against Fallujah in hopes of pacifying Sunni areas north and west of the capital so elections could be held there Jan. 30.
In London, Saleh, said delaying the election would have "serious ramifications to the political process" and would bolster the insurgents' cause.