A car bomb killed two people in central Baghdad yesterday and wounded 26, a police source said, raising the death toll to 21 after insurgents ambushed an Iraqi army patrol north of Baghdad on Saturday, killing 19 soldiers.

This latter incident is believed to have been a well-planned attack, a day after the Pentagon announced 10 US Marines were killed by a bomb west of the capital. The bomb was placed under the car, parked in Tahrir Square in the city centre, but the target of the attack was not immediately clear, the source said

The Iraqi soldiers were travelling in a five-vehicle patrol near Baquba, 60 km from Baghdad, when they were hit by a roadside bomb. Immediately afterwards, gunmen opened fire.

Police sources said 19 soldiers were killed and that they were from southern Iraq where the population is largely Shi?ite Muslim, potentially adding a sectarian element to the attack.

The attack in Baquba, where there has been a surge in guerrilla activity over the past three weeks, followed the assault on the Marines near the former rebel city of Falluja on Thursday, the deadliest attack on US troops for four months.

An Iraqi militant group posted a video on Saturday which showed what it said was an explosion near Fallujah that killed the 10 US Marines. The group, the Islamic Army in Iraq, is among several insurgent organisations battling US troops and Iraqi forces.

The brief video shows a Humvee, flanked by what look like US troops, travelling slowly down a street when an explosion engulfed the vehicle, sending clouds of dust into the air and bystanders fleeing. An off-camera voice was heard saying ?Allah is Great? repeatedly.

The video?s authenticity could not be verified but it was posted on a Web site generally used by insurgents to claim attacks. Al Jazeera television had earlier aired the video.

Sectarian strikes

The Marines were on a foot patrol near a factory when they were struck by a bomb made out of several artillery shells strung together, the Marine Corps said. The deaths raise to more than 2,120 the number of US troops to have died in the war.

The deaths come amid a rise in insurgent violence ahead of elections set for December 15, and amid growing tensions between Iraq?s Muslim sects. In a move that could aggravate those tensions, the country?s top Shi?ite cleric has urged Shi?ites to turn out and vote for religious candidates on election day.

US commanders have said they expect an increase in violence in the build up to the election. Over the past three weeks there has a been a series of car bombings and suicide attacks that have killed more than 230 Iraqis, mostly civilians.

Many of the strikes have been sectarian in nature, with Sunni Arab insurgents targeting the Shi?ite majority in an attempt to push the country closer to civil war.

On Saturday, Ayatollah Ali al-Sistani, the country?s most influential Shi?ite cleric, issued instructions to followers urging them to vote in the election and to cast their ballots in favour of religious candidates from the principle lists.

The instructions are likely to have an impact on voting and looked like a coded endorsement of the main Shi?ite bloc contesting the elections, the United Iraqi Alliance, winner of January?s poll.

According to Sistani?s office, the reclusive scholar has instructed believers to do three things: turn out to vote; avoid voting for any list whose leader is not religious; and avoid voting for ?weak? lists so as not to split the Shi?ite vote.

Sistani holds huge sway over Iraq?s 60 % Shi?ite majority. His instructions could dent the hopes of secular Shi?ite candidates such as Iyad Allawi and Ahmad Chalabi.

Allawi, Iraq?s first prime minister after the fall of Saddam Hussein, is mounting a strong challenge to the ruling Shi?ite Islamist coalition, which was originally formed at Sistani?s urging to contest the first post-Saddam election in January.

Saddam Hussein?s Baath party, responding to a speech by US President George W. Bush outlining a ?strategy for victory? in Iraq, on Saturday said Bush needs only to think about how to pull out his troops from Iraq. ?You are losing the war, losing your occupation scheme in Iraq, losing your false claims of freedom(...) just as you are losing your regional and global scheme,? said the statement, posted on a Web site used by Baathists.

Separately, four Western aid workers kidnapped a week ago appeared in a second militant video aired by Al Jazeera TV. They face death unless 12,000 prisoners in Iraq are released by December 8.

HOSTILITY

Angry Shi?ites pelt Iraq ex-PM Allawi

■ A crowd hurling shoes, rocks and tomatoes forced former Prime Minister Iyad Allawi to cut short a visit yesterday to Iraq?s holiest Shi?ite shrine during a campaign trip to the city of Najaf, police officers said. A spokeswoman for Allawi, a secular Shi?ite, said she had no information on the incident but confirmed that Allawi, who is challenging the ruling Shi?ite Islamist Alliance bloc at next week?s parliamentary election, had been in Najaf during the day. A police captain, speaking on condition of anonymity, said a large crowd of worshippers at the Imam Ali mosque hurled sandals and shoes at Allawi ? a grave insult in Iraqi culture. A second police officer said some of Allawi?s bodyguards fired in the air to disperse the crowd and that also threw rocks, sticks, tomatoes and other projectiles. Police also intervened to break up the disturbance, he said.

Faris AL-MEHDAWI