Insurgents killed at least 19 Iraqis and bombed polling stations on Thursday in a fierce campaign to wreck Sunday's general elections.
With the election only three days away, violence has been escalating. The flurry of attacks, following a helicopter crash that killed 31 US troops on Wednesday, were concentrated on the heartland of Iraq' minority Sunnis.
In the deadliest attack on Thursday, a car bomb hit an Iraqi army patrol near a polling station in Samarra, a mainly Sunni Muslim city. Seven Iraqis were killed and five others wounded, police said.
In Baquba, 60 km northeast of the capital Baghdad, a suicide car bomb hit the headquarters of a provincial government, killing five people.
South of Baghdad, in the so-called triangle of death, a homemade bomb killed five Iraqis and injured 15 on the road between Mahmudiyah and Latifiyah.
Gunmen killed a policeman in an attack in Musayyib, south of Baghdad, and a roadside bomb killed a police officer in Baiji.
One US Marine was killed in action and four others wounded while conducting security and stability operations in Babil Province, according to the US military.
Three small bomb blasts occurred at polling stations in Iraq's southern city of Basra on Thursday, but no one was hurt, according to a British army spokesman.
With about 40 polling stations destroyed by insurgents, even the distribution of ballot boxes for Iraq's 13 million eligible voters, about half of the country's population, underscored the grim security situation.
In the Shiite holy city of Najaf, Iraqi police, US troops and Iraqi security forces sealed off an area within a one-kilometer perimeter around a school to be used as a polling station when ballot papers were brought in.
Several guerrilla groups, including a faction led by Abu Musab al-Zarqawi, have declared war on the poll, vowing to kill anyone who votes.
The militant group Army of Ansar al-Sunna issued a "final warning," saying anyone who votes would be marked for death, either during or after the election.
"Those who don't pay heed will have only themselves to blame," the group said in a statement on the Internet.
The faction led by al-Qaida ally Abu Musab al-Zarqawi said Thursday on a website that it had executed a candidate of interim Prime Minister Iyad Allawi's party and a video would be released later.
In the past two months, 22 members of Allawi's party were killed, according to party official Imad Shbib.
In the countdown to the election, the Iraqi security forces bore the brunt of the attacks. While US forces worked to quell the insurgency, the US State Department has asserted that Iraqis will take "paramount" responsibility in providing security for the election.
"I think you will see on Election Day that most of the security is being provided by the Iraqis and the Iraqi forces," said State Department spokesman Richard Boucher.
Boucher said US President George W. Bush was confident that the world would recognize the legitimacy of the election despite worries that it would be marred by a boycott by Sunni Muslims and violence.
US military commanders and Iraqi officials predict that violence will flare up as insurgents attempt spectacular new attacks.
Meanwhile, US President Bush and interim Iraqi President Ghazi al-Yawar on Thursday discussed efforts to get Iraqis to vote despite growing violence. This was the seventh conversation that Bush has had with Iraqi leaders since the beginning of 2003.
Despite Bush's confidence in the election, Turkish Prime Minister Tayyip Erdogan said on Thursday that the election would not be fully democratic since one major ethnic group is to be absent.
Russia, a major player in the arena of world politics, said on Thursday that it would not send observers to monitor the election due to the security situation there.