United States infantry in southern central Iraq have been engaged in heavy fighting with Iraqi militiamen for control of the strategically important town of Samawah. BBC Correspondent Gavin Hewitt, with the Third US Infantry Division, sent this report from the frontline.
US troops are fighting for control of a vital bridge
All morning there has been an intense battle going on for the town of Samawah.
This is a crucial staging post on one of the convoy routes from Kuwait up to the outskirts of Baghdad.
What happened this morning was that some of the Iraqi units inside the town - the Fedayeen who are intensely loyal to Saddam Hussein - began moving towards the highway.
Quite a major battle has been taking place for the last two hours inside this town.
American tanks and fighting vehicles headed towards the centre of the town where they think there are about 1,500 Fedayeen who are guarding a bridge across the Euphrates.
It has been an intense battle, heavy guns have been used, tank shells have been used - at least seven Apache helicopters have come in trying to attack the Iraqi positions.
Militia holed up in town centre
I can see black smoke rising above the main area of the city in at least three places.
I am about three kilometres away - I can still hear the sounds of fighting - particularly the sounds from the Bradley fighting vehicles attacking buildings where they believe this Fedayeen militia is holed up in the centre of town.
US armoured vehicles have engaged the Iraqi forces
What the US want to do is secure this town so the logistical "trains" that are coming up the road from Kuwait can pass for the crucial battle in Baghdad.
For the last three hours not a single American truck has been able to move north because this has been such a fierce fire-fight.
Earlier, the armoured column I am with went for about 12 hours almost non-stop, making tremendous headway, then they encountered resistance - and that resistance has been really fierce.
There is no question that the Saddam loyalists are making a fight of this.
Among the troops here, everybody is saying "this is not what we expected." They did not intend to take these towns but they needed to secure them in order to push up towards Baghdad.
The original battle plan was take Baghdad, decapitate Saddam Hussein's regime, and the rest would follow.
It has not worked out like that, because some of these units that are intensely loyal to Saddam Hussein are positioned in these towns and are prepared to fight and to try to draw the Americans into guerilla-style fighting in town centres - which also risks alienating local populations.
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