Suicide bombers have killed 20 members of Iraq's fledgling security forces near a US marine base west of Baghdad and at a checkpoint to the north amid a spate of insurgent attacks across the country.
The surge in violence underlined the scale of the task facing the US military and Iraqi interim government, which have sworn to quell rebels ahead of elections due in January.
Rebels killed two Turkish truck drivers and wounded two in a convoy attack near the northern city of Mosul.
Six US soldiers were wounded when guerrillas set their armoured vehicle ablaze on a highway leading to Baghdad airport in what the US military said was a roadside bomb blast.
Hospital sources said 16 Iraqi police were killed and up to 40 wounded in the suicide bombing near the marine base west of Baghdad. He said it occurred at about 7 a.m. ( 5 a.m. Irish time) at an Iraqi police post near Al Asad camp.
Hospital staff in the nearby town of Haditha said they had received more than 50 casualties after the blast.
A suicide bomber blew up his vehicle near a checkpoint manned by Iraqi National Guards in the village of Ishaqi, near Samarra, north of Baghdad, killing four guards. A guard officer said six guards were also wounded in the attack.
Insurgents fired two mortar rounds in central Baghdad, killing two civilians and wounding one, witnesses said.
There was no let up in violence elsewhere across the Sunni Arab heartland of central Iraq.
Rebels killed two Turkish truck drivers and wounded two in a convoy attack near the northern city of Mosul, police said.
Six US soldiers were wounded when their armored vehicle was hit by a roadside bomb on a highway leading to Baghdad airport. Insurgents also fired two mortar rounds in central Baghdad, killing two civilians and wounding one, witnesses said.