Seven US soldiers have been killed in a bomb attack by insurgents in Baghdad.
US troops in Iraq now face daily attacks by insurgents
The US military said their Bradley armoured vehicle hit a roadside bomb in the north-west of the Iraqi capital on Thursday evening.
In a separate incident, the military reported that a marine had been killed in Anbar province, west of Baghdad.
The attacks come as Iraq's authorities say the state of emergency which gives them special powers to fight rebels is being extended for another month.
The seven US soldiers were on a routine security patrol in their vehicle when the explosion occurred at 1800 local time (1500 GMT), said US military spokeswoman Captain Patricia Brewer.
"All of the occupants were killed," she said.
Violence has been steadily growing in Iraq in recent weeks ahead of the 30 January election, claiming dozens of lives every day.
Recruits gunned down
In a separate development, it has emerged that 18 Iraqi men recruited to work at a US base near Mosul have been murdered. Their bodies were found in a field outside the northern city.
Violence continued with the discovery of 18 bodies near Mosul
The labourers, all Shia Muslims, had apparently been recruited by a contractor from a casual labour market in Baghdad.
They were sent up to the Mosul area in minibuses in early December, ostensibly to work at the US military base there.
Whether this was a deliberate trap is not known, but the buses were intercepted by gunmen and the workers disappeared, said the BBC's Jim Muir in Baghdad.
The bodies, now in a state of decomposition, were brought back down to Baghdad where they were claimed by relatives and taken home to the south for burial.
Mosul, a predominantly Sunni city 360 km (225 miles) north of Baghdad, has recently been a centre of insurgent activity.
A suicide attack on 21 December in a mess tent at a US base near Mosul killed 22 people, including 14 American soldiers.
Dealing with violence
The extension of the state of emergency was needed because "gangs of terrorists" continued to disrupt the political process, Iraqi interim Prime Minister Iyad Allawi said.
The move comes as no surprise in these circumstances, correspondents say.
The emergency rule was first imposed for two months in November last year ahead of a major assault on the insurgent stronghold of Falluja.
The measures include powers to impose curfews and close borders and airports.
They also allow the government to detain people suspected of being part of the insurgency without following normal legal procedures.