BAGHDAD, Sept 15: American troops found three bodies and their severed heads north of Baghdad on Wednesday while 13 people died in clashes in Ramadi, two more in a car bomb attack and two Iraqis employed by the US Army were shot in the north.

More than 350 people have been killed so far this month alone, spurring the US authorities to switch more than three billion dollars into boosting security at the expense of earmarked reconstruction projects.

The headless, decomposing corpses, thought to be of Iraqi civilians, were discovered on a roadside with inscriptions carved into them, before their remains were put in bags and taken to Balad.

Authorities believe they had been dead for about five days. Further north, militants shot dead two Iraqi builders employed by the US military, not far from the northern oil capital of Kirkuk, police said.

Just south of Baghdad, in the militant bastion of As Suwayrah, an Iraqi national guardsman and civilian were killed and 10 people wounded in a car bomb attack, the interior ministry said.

Another bomb in Baquba, north of Baghdad, wounded four policemen and a civilian, according to police and a local doctor. On Tuesday, a massive car bomb outside the main Baghdad police headquarters killed 47 people, while 12 policemen and their driver were shot dead in Baquba - the latest attacks on the US-sponsored Iraqi forces. Both assaults were claimed in the name of the Tawhid wal Jihad group of alleged Al Qaeda operative Abu Mussab al Zarqawi.

CLASHES IN RAMADI: The health ministry said 13 people were killed and 17 wounded in fresh clashes in the western city of Ramadi, where exchanges of fire pitted guerillas against US marines for the second consecutive day.