Two US soldiers have been reported killed and three others wounded in two separate attacks in Baghdad.
The US military said a roadside bomb killed one soldier and injured three in south Baghdad while another soldier was killed in a small arms fire attack in the north of the city.
Earlier, at least six people died in incidents in Iraq, just two days before the elections there.
A suicide bomber killed four people at a Baghdad power station this morning and an Iraqi soldier and policeman were killed in attacks in the troubled cities of Samarra and Kirkuk.
In the northern city of Mosul, a ban on cars has been in operation since yesterday afternoon, while the Salaheddin province will impose a curfew tomorrow night.
The head of police in Najaf strongly urged shops to shut, and people to stay at home - a night-time curfew will be in effect there during the weekend.
