"Some 150 rebels were killed," commander Major James Gallivan, operations officer in the US Army 3rd Armored Cavalry Regiment, which is leading the attack on the northern rebels' stronghold, said late on Monday.

"A total of 407 bad guys (rebels) are now held in custody ... . These are the ones kept for further screening," he added, pointing out that many other men were released after being temporarily detained, after finding no evidence of their involvement in clashes.

Iraqi and US troops had tightened their grip on the rebel stronghold of Tal Afar as fighters wilted in the face of overwhelming firepower deployed by the 10,000-strong assault force.

The 6000 Iraqi and 4000 US troops had intensified their offensive late last week after days of deadly clashes failed to dislodge rebels from Sunni Arab neighbourhoods of the ethnically divided town.

Classic guerrilla tactics

Colonel Greg Reilly said the fighters were using classic guerrilla tactics, melting away whenever confronted with superior numbers. "They went into hiding, avoiding us. That's why there is no fighting ... . They are not putting up a fight," he said.

Displaced Tal Afar residents walk
outside their tents at a camp

Aljazeera reported on Monday that al-Qaida official in Tal Afar, Hassan Muhammad Ali, also known as Abu al-Qasim, had been killed along with two of his colleagues by US air strikes.

Iraqi Interior Minister Jabr Solagh said troops had dealt what he called a severe blow to al-Qaida in the town, prompting the network to threaten the use of chemical weapons, according to him.

On Monday night, a huge car bomb exploded outside a popular restaurant in Baghdad's upscale Mansour neighbourhood, witness said. Hospital officials reported at least one person killed and 17 wounded.

A doctor at Yarmuk hospital said most of the victims were women.

US ultimatum

Meanwhile, US troops continued to round up all men of fighting age in Sunni neighbourhoods where the fighters had held sway, after issuing an ultimatum for male residents to leave last Tuesday.

Masked Iraqi informers advised commanders which detainees to retain in custody and which to release.

Around 10,000 Iraqi and US
troops are in the town

Near the grain silos on the edge of town, US troops brought in dozens of men in traditional robes one by one for vetting by the informers. All were handcuffed. Some were also blindfolded.

Reilly said around half of the suspects picked up by his unit had been freed after informers gave them a clean bill of health, while about 150 had been arrested and remain in detention.

Other informers poured through files prepared by US troops on each detainee but many had difficulty reading the names scribbled down in English.

Foreign fighters?

US commanders have charged that many of the fighters in Tal Afar are foreign fighters who had turned the town into a staging post for volunteers infiltrating Iraq across the porous border with Syria further west.

But Reilly acknowledged that the 40 tanks and 40 armoured personnel carriers of his Tiger Squadron had actually been moved away from the town of Sinjar near the border where they were normally deployed to join the assault on Tal Afar.

Troops are using Iraqi informers
to identify suspected fighters

Sunni neighbourhoods of Tal Afar resembled a ghost town on Monday.

In the southeastern Saray district, which had been the scene of some of the fiercest fighting, a US Abrams tank manoeuvred through deserted streets.

As the fighters melted away, the fear which had stalked Tal Afar's large Shia Turkmen community for months finally eased and officers of the town's Shia-dominated police force returned to their posts.

Sectarian tensions

But with the removal of the threat that had prompted scores of Turkmen families to flee for the safety of Shia areas of central and southern Iraq, it was the Sunnis' turn to worry about sectarian retribution.

"We don't fear you. We fear the [Iraqi] police," Hazem Saeed, 50, told a US patrol in the Sunni neighbourhood of Qadisiyah.

"They went into hiding, avoiding us. That's why there is no fighting... They are not putting up a fight"

Colonel Greg Reilly,
US Army

"We don't want them [the police] here," echoed fellow resident Mohammed Yunis.

But Tal Afar police officers rejected suggestions that Sunni detainees risked being tortured by their men, in retaliation for the intimidation which had kept the force off the streets for weeks.

"We hand detainees directly to the Americans," Hussein Ali
insisted.

Al-Zarqawi threat

Fighters responded to the assault in a series of internet statements promising retaliation, including a voice recording attributed to al-Qaida's Iraq leader Abu Musab al-Zarqawi that accused the US military of using chemical weapons in the assault.

"O nation of Islam, your heroic children are writing with their own blood the most beautiful of epics ... in the towns of al-Qaim and Tal Afar ... where your Crusader enemies are using more destructive weapons including poison gas," the voice said.

Sectarian tensions are running
high in ethnically mixed Tal Afar

Another al-Qaida-linked group threatened to retaliate against US forces with chemical weapons.

An internet statement posted in the name of the Jaish al-Taefa al-Mansura, or Army of the Victorious Community, warned of reprisal attacks using "non-conventional and chemical weapons ... developed by the mujahidin ... unless the armed onslaught against the city of Tal Afar stops within 24 hours".

A third statement posted by the Islamic Army in Iraq - a group that has previously been linked to capturing and killing foreigners in the country - offered rewards to fighters who assassinate the Iraqi prime minister, interior minister and defence minister as revenge for the Tal Afar operation. 

None of the internet postings' authenticity could be verified.