IRAQI elite forces have moved out of Baghdad to take on advancing US troops, as coalition commanders sought to put a stranglehold on Saddam Hussein's regime.

Republican Guard troops have been moving out to combat the American spearheads and protect the city's airport, according to reports originating from US spy planes.

US military sources said the forces were from the Hammurabi Mechanised Division.

They also said two Iraqi counter-attacks on a vital bridge 20 miles south of Baghdad - the closest point to the capital that US ground forces are known to have reached - had been repulsed.

US commanders claimed yesterday to have effectively destroyed two of the other divisions of the Republican Guard during the coalition's two-pronged advance on Baghdad from the south - a claim denied by Iraq.

An American Black Hawk helicopter has been shot down by small arms fire south of Baghdad, killing seven of the 11 troops on board. The other four personnel in the aircraft, which was downed near Karbala, the scene of fierce fighting between the US 3rd Division and Iraqi forces, were wounded. Search and rescue teams were on the scene.

An American FA-18 Hornet fighter bomber has been shot down by a surface-to-air missile in southern Iraq. It is not known what happened to the pilot.

Baghdad has come under repeated air attacks again, with a huge explosion being heard in the city centre at about 2am today.

The 19-year-old American former prisoner of war, Private First Class Jessica Lynch, who was rescued in a daring raid by US special forces from a hospital in Nasiriyah, has been taken to a US military hospital in Germany.

Updated: 09:05 Thursday, April 03, 2003