BAGHDAD, Jan 29: Insurgents vowing total war on Iraq's landmark polls killed 19 people on the eve of the vote on Saturday and threatened a bloodbath on election day.

Interim Prime Minister Iyad Allawi urged the country's fractious religious and ethnic groups to defy "enemies trying to break us and to break our world" and to vote in Iraq's first multi-party elections in half a century.

Even as US-trained security forces barricaded streets, sealed Iraq's borders and closed Baghdad airport, more than a dozen polling stations were attacked and bloodshed continued to overshadow the final electoral countdown.

With just a day to go before the polls, a suicide bomber blew himself up outside a US-Iraqi security centre in the town of Khanaqin, northeast of Baghdad near the border with Iran. The US military said three Iraqi soldiers and five civilians were killed. No Americans were hurt.

Al Qaeda's ally in Iraq, led by Jordanian militant Abu Musab al-Zarqawi, claimed responsibility and threatened mayhem when voters go to the polls from 7am (0300 GMT) on Sunday.

"For the last time, we warn that tomorrow will be bloody for the Christians and Jews and their mercenaries and whoever takes part in the (election) game of America and Allawi," it said in a statement posted on an Islamist Website.

Most other attacks were concentrated in the Sunni heartland north of Baghdad where the insurgency has been fiercest and where many once-privileged Sunnis plan to boycott the election. Three civilians died in a roadside bombing in the city of Samarra. A rocket attack on an Iraqi army base in the neighbouring town of Duluiya took the lives of three soldiers.

Insurgents killed a security guard when they blew up an explosives-laden donkey cart outside a polling station in the town of Sharqat, south of Mosul, witnesses said.

Mortar rounds hit a voting centre in the refinery town of Baiji, wounding four guards, after two other sites were dynamited there overnight.

Three Iraqi contractors abducted a week ago were found shot dead in the town of Balad. Insurgents brand all Iraqis working with US forces as collaborators and have killed hundreds.

The election is the cornerstone of the Bush administration's plan to transform Iraq from dictatorship to democracy after the fall of Saddam Hussein in April 2003. But it risks fuelling the insurgency and fomenting sectarian strife.

With tension high in the capital, bursts of gunfire echoed in some areas and insurgents fired rocket-propelled grenades at the fortified Baghdad Hotel. There was no word of casualties.

South of Baghdad, a Iraqi woman and her child were killed when mortar rounds targeting a US base struck their home.

US troops killed two Iraqis in a car near the western city of Ramadi, according to witnesses. The circumstances were not immediately known.

Fierce fighting between insurgents and US troops raged around Ramadi, one of the most volatile Sunni cities.

Zarqawi's group has declared holy war against the election, calling voting stations "centres of infidelity and immorality" and warning Iraqis to stay away.

The US military said insurgent attacks had more than tripled to 98 on Thursday from 29 last Saturday.

Iraqi President Ghazi al-Yawar, a Sunni Arab, predicted that up to two-thirds of the country's 14.2 million eligible voters would cast ballots. The US-backed interim government has said it hopes for a turnout of at least 50 per cent.

"Of the people who will not vote, the majority of them are scared of violence," Yawar said. He issued a statement clarifying what he meant after earlier remarks seemed to suggest he thought most Iraqis would not vote.

Yawar said that any political process that did not include Sunni Arabs, Kurds and Shias - Iraq's three main groups - would be invalid.

Most candidates have kept their names secret because of the violence and intimidation. Authorities have also kept the location of polling stations secret until the last moment.

The turnout is expected to be lowest in Sunni Arab areas, where the insurgency has been bloodiest. Sunnis, the backbone of Saddam's ruling class, make up 20 per cent of the population.

Iraq's 60 percent-majority Shias, oppressed for decades under Saddam, are expected to dominate the polls, bringing them to power for the first time.

Kurds, who make up nearly a fifth of Iraqis, see the ballot as a chance to enshrine their autonomous rule in the north.

Despite violence, Allawi, a secular Shia, told Sky television Iraqis must "take their own fate in their own hands".

Many people vowed to brave the threats, but others were afraid of being targeted at the polls or afterwards, when indelible blue ink daubed on their index fingers to prevent multiple voting could mark them for death.

A survey by Zogby International showed 76 per cent of Sunni Arabs did not plan to vote. Only nine per cent said they would definitely vote. By contrast, 80 per cent of Shias were expected to take part.-Reuters