BAGHDAD Police found nine bodies and 10 severed heads in an abandoned field north of Baghdad on Tuesday, in a region where U.S. and Iraqi forces were pressing ahead with offensives against al Qaeda forces.
In the northern city of Mosul, a suicide car bomber killed one civilian and wounded 15 others in an attack on a U.S. convoy, U.S. and Iraqi security officials said.
The U.S. military said none of its soldiers were wounded in the latest attack in Mosul, where extra Iraqi troops and police have been sent for what Iraqi Prime Minister Nuri al-Maliki has called a "decisive" final push against al Qaeda.
But Major-General Mark Hertling, commander of U.S. troops in northern Iraq, cautioned against such descriptions of the fight against al Qaeda, saying the Sunni Islamist militants could easily regroup elsewhere as they had done in the past.
"I'm just not confident enough to say this is the final push against AQI (al Qaeda in Iraq) ... in Mosul," Hertling said.
"What we can say is that there has been an attempt by AQI to gain control of Mosul. We have to not allow them to get that stronghold," he told Reuters by telephone.
Extra Iraqi troops, backed by tanks and helicopters, began arriving in the city on Sunday but the Iraqi government has so far not given full details about numbers involved. The U.S. military says its efforts there are part of a continuing push.
Five U.S. soldiers were killed on Monday by a roadside bomb in a coordinated ambush in Mosul, which U.S. commanders regard as al Qaeda's last major urban stronghold in Iraq.
Police found the bodies and severed heads in a field in Muqdadiya, 90 km (55 miles) northeast of Baghdad in Diyala, one of four northern provinces where U.S. and Iraqi forces have launched offensives against al Qaeda.
Police said some of the nine complete bodies were partially decomposed while others had been killed more recently. The bodies were all handcuffed and blindfolded and had bullet wounds, police and hospital officials said.
The 10 heads found nearby were all also blindfolded, some with bullet wounds, said Ahmed Fouad, the chief of the morgue in Baquba hospital. Baquba is the provincial capital of ethnically and religiously mixed Diyala.
Hertling said beheadings had been used before by al Qaeda to intimidate residents in Muqdadiya. "We know that they have paraded heads through that area," he said.
On January 9, five severed heads were found, all with messages scrawled in blood in Arabic on the foreheads warning that volunteers working with U.S.-backed neighbourhood patrol groups would suffer the same fate.
Sharp falls in violence across Iraq have been attributed to the neighbourhood units, formed by mainly Sunni Arab sheikhs who turned against al Qaeda because of its indiscriminate killings, and to an extra 30,000 U.S. troops deployed last year.
The neighbourhood patrols have become frequent targets. The leader of one such unit in Taji, just north of Baghdad, was killed by a bomb in his car on Monday, local officials said.
In a separate incident on Tuesday near Mosul, 390 km (240 miles north of Baghdad, unidentified gunmen killed two off-duty police and wounded two others, police said.
Tens of thousands of U.S. and Iraqi soldiers are taking part in operations in Iraq's northern provinces, part of a wider offensive that was launched early this month.
Attacks across Iraq have fallen 60 percent since last June, when the extra troops became fully deployed, but northern Iraq remains the biggest security headache for U.S. and Iraqi forces.
Al Qaeda, blamed for most large-scale attacks in Iraq, and other insurgents regrouped in the north after being squeezed out of their former strongholds in western Anbar province and from around Baghdad during security crackdowns last year.
The new push in Mosul was announced after a huge blast in a building the U.S. military said had been used by al Qaeda to store weapons and explosives. Up to 50 people were killed.
(Editing by Jon Boyle)