US special forces set out Tuesday from this town in Iraqi Kurdistan with Kurdish fighters to track down militants of the Ansar al-Islam group who might have survived the bombing and the onslaught on their stronghold.

The US forces kept mum on the location of their hunting ground, but a Kurdish official said it was a mountainous region on the border with Iran because "they have nowhere else to go" after the Islamic Republic "closed its border."

All the villages along the wide road leading to the Iranian pass have been "cleaned up," he said.

US missiles demolished blockhouses previously used by Ansar al-Islam ("Supporters of Islam"), to keep Kurdish forces at bay.

Caves that could be used as hideouts were inspected and emptied, and Ansar's headquarters were painted with the colors of the Patriotic Union of Kurdistan (PUK), the group that administers this part of northern Iraq captured from Iraqi President Saddam Hussein's army after the 1991 Gulf War.

Ansar al-Islam in turn captured a few dozen square kilometers (dozens of square miles), in September 2001, establishing an Islamist stronghold within the Kurdish enclave.

American forces and Kurds have said they had found confirmation of the connection between Ansar and Osama Bin Laden's al-Qaeda terror network, including propaganda material and passports.

In their campaign to topple Sadddam, the United States had used Ansar's presence in Iraq to charge the Iraqi president was supporting terrorism, although the Islamists were not deployed in areas under his control.

Ansar's appearance coincided with the September 11 attacks on the United States. It established rigid Islamic rules in the area under its control, and launched a fierce campaign against the PUK, carrying out bloody incursions and attacks on Kurdish territory.

Kurdish estimates of Ansar's losses from the US-Kurdish onslaught at between 150 and 300 dead.

"Two were killed yesterday (Monday). They faked wanting to surrender and killed one of ours," said a Kurdish official in Chamchamal.

Dozens of Ansar militants have also been reported captured, including 35 on Monday alone.

But those figures cannot be verified, just like the figure on Ansar's pre-war strength put by some at 300 men and by others at 1,000.

Among those said to be at large are the two leaders of the group, Abdullah Aishafey and Tahseen Ali Abdulaziz, hiding with followers in the mountains.

"Our task is to find them, force them to surrender or take them out," said a Kurdish chief guiding the US forces' hunt. The Iranian border makes their mission easier and more complicated at the same time.

Complicated because the hunters have to avoid contact with Iranian forces, and easier because, by all Kurdish accounts, Iran has closed its border for the fugitives, and by some, opened fire on Ansar militants using the smugglers' tracks to flee.

The PUK in the past accused the Iranians of backing Ansar. But Tehran has always denied that and stated its neutrality in the US-led war on Iraq, concerned that the American noose would tighten around it.

It has also denied hosting al-Qaeda fugitives after the US campaign in Afghanistan.

A member of the Kurdish leadership in Halabja, "Mam" Osta Aziz, did not however rule out that "some" Ansar members could have escaped to Iran without the authorities knowing about it.

SPACE.WIRE