On the northern front Iraqi positions near the demarcation line between Kurdish- and Iraq-held territories came under fire from US and British invasion forces for the third night running early Monday. The bombardments, which were heard in the Kurdish town of Kalak, some 40 kilometers (25 miles) east of the city of Mosul, began shortly after midnight local time (2215 GMT Sunday).

Kurdish forces are now slowly advancing on the northern Baghdad-controlled oil city of Kirkuk.

Iraq Pulls Back on Northern Front

Iraqi soldiers fell back at least 12 miles from the Qushtapa checkpoint to apparently regroup near Perdeh - also known as Altun Kupri - about 30 miles from Kirkuk.

The town has an important bridge over the Little Zab River. Bypassing the bridge would require coalition forces to make difficult and potentially dangerous detours through rolling hills where Iraqis could stage guerrilla-style ambushes.

Kurdish commanders believe the retreat is part of attempts to solidify Iraqi defenses around Kirkuk. Earlier this week, Iraqi troops made a similar pullback east of Kirkuk.

Kurdish leaders, meanwhile, have pledged not to stage any independent attacks for the time being.

Kurds Clash with Ansar al-Islam

In the eastern part of the Kurdish zone, militia backed by U.S. forces took control Friday of territories held by the Ansar al-Islam, a group accused by the United States of maintaining ties to Saddam.

In fighting with Ansar al-Islam, at least two members of the Patriotic Union of Kurdistan, or PUK, were killed, and 22 others injured. About 40 Ansar fighters were killed and at least one was captured, The Washington Post reported, citing medical officials.

U.S. invasion forces have been bombing Iraqi and Ansar-al Islam targets in northern Iraq and Mosul and Kirkuk for several days. More aircraft could be heard flying over Halabja along the Iranian border late Friday.

U.S. Envoy Works to Prevent Turkish Incursion in Northern Iraq

U.S. special envoy held talks at Turkey's foreign ministry Saturday aimed at easing Turkish concerns about developments in northern Iraq and preventing Turkey from sending its own troops there.

Turkey, a U.S. NATO-ally, has said it could move into northern Iraq to prevent a possible refugee crisis or prevent Iraqi Kurds from forming an independent state. Washington fears friendly-fire incidents and clashes between Turkish and Iraqi Kurdish forces.

Zalmay Khalilzad, White House envoy to the Iraqi opposition, said his talks were aimed at solving those issues, the Anatolia news agency reported.

PHOTO CAPTION

A paratrooper from the U.S. Army 173rd airborne stands guard as others climb onto a truck to deploy from Harir airbase north of Arbil, northern Iraq on March 29, 2003.