At least 12 people have been killed in Iraq in a number of attacks a day after Prime Minister Nouri Maliki announced a new drive to boost security in Baghdad.

Four civilians were killed in a mortar barrage in central Baghdad and an attack on an education ministry official killed two bodyguards.

A car bomb in Hilla, south of Baghdad, killed one person and injured 12 more.

Earlier Iraq's army said it killed 30 militants in a Baghdad clash thought to mark the start of the new drive.

In other violence:

· Three US airmen assigned to a civil engineers' division died and another was injured in a bomb attack in Baghdad

· A US soldier died in small arms fire, also in Baghdad

· Two Iraqi interpreters working with a US security contractor who disappeared on Friday were found dead in the southern city of Basra. Another man, a US national is still missing

'New strategy'

Prime Minister Maliki said Iraqi forces would carry out the new campaign, backed up by US forces on call.

This comes just days before President George W Bush is due to announce his new strategy for Iraq.

He has said he is in favor of sending thousands more soldiers to Iraq, despite opposition to the idea in the new Democrat-controlled Congress.

Photo caption

Iraqi policeman in Baghdad