THE skies over Umm Qasr burned orange last night as the allies brought in tanks, aircraft and heavy artillery in an attempt to bring to an end a three-day siege.

The scale of the resistance met by allied forces in Iraq’s only deep-water port has stunned coalition forces.

Intelligence officers had assured the US Marines that they would meet at most a handful of Iraqi diehards refusing to surrender when they marched into Umm Qasr, and on Friday allies spoke of “pockets of resistance”.

By last night that assessment had proved so wide of the mark that Marine commanders, edging nervously through the backstreets of this decrepit port, refused to predict how many more gunmen might be waiting for them. One officer said: “The fighting has got worse with each day. So much for the walkover we were told to expect.”

What started as a skirmish with a few armed Iraqis near a port in the south turned into the Battle of Umm Qasr, a full-blown pyrotechnic display of mainly American military muscle. In spite of 150 US Marines, four main battle tanks, an FA18 warplane and an RAF Harrier jump-jet, the Iraqis stood firm.

By nightfall their position still had not been silenced, raising questions about how fast US troops will be able to mop up resistance elsewhere in Iraq, especially in Baghdad.

“I guess you can call it a battle,” Staff Sergeant Nick Lerma, 33, said in the Texan drawl of his hometown, San Antonio. “It started off small, but it got pretty big.”

Yesterday the allies waited until dark to unleash their barrage on a band of Republican Guards thought to be hiding in some dilapidated warehouses in the port.

There were a dozen explosions in swift succession, shaking buildings as far as six miles away, which Marine commanders were confident would finally wipe out the resistance that was proving an embarrassment to their efforts to open up Iraq’s only deep- water port.

What happened next astounded allied commanders as Iraqi units sent back a volley of artillery fire.

Like a maestro conducting an orchestra, Staff Sergeant Lerma spent most of yesterday striding on an earth berm 900 yards from the target, egging on his young troops from 1 Platoon of Fox Company.

Urging them in the bluest of language to stay behind cover and to don helmets, he stalked behind them, talking one moment into his radio microphone and then shouting commands the next. “I have got a bunch of young men here just out of training and they are like a load of young dogs all straining at the leash, so they take some handling.”

It was Staff Sergeant Lerma who called for the deployment of two Javelins to launch rockets to destroy the target. One missed, but the other slammed into the building.

“Thank God we fired those things,” Lance Corporal Samuel Balderama, 20, from Baltimore, Maryland, said. “They weigh 40lb each, so now we have two less to carry home.”

At around midday two RAF Harriers dipped towards the rusting storage depot where the main group of Iraqis was holed up. The first 500lb bomb fell just wide of the mark, but moments later the second went home.

On the outskirts of the port, which British troops need to open swiftly to get the humanitarian operation under way, US Marines swung a line of Bradley fighting vehicles towards a rusting warehouse where they believed that a group of officers was holed up.

In the street behind them, there were seven Iraqi bodies lying in the dust. All that was seen of Umm Qasr’s 4,000 frightened residents was the occasional glimpse at a window of one being used as a human shield by gunmen.

By late last night the US Marines were thinking of calling in yet more weaponry, this time Cobra attack helicopters, but they had too little time to organise the mission. Instead, three ½in-calibre sniper rifles were used and they were banging away by nightfall, but still not neutralising the target. “Fire! Fire!” a soldier screamed. “They are using binos to spot against us. Fire! Fire!”

If the display of firepower had not been so devastating, the whole operation might have been comical.

“If the Americans are like this when they have one building to deal with, what are they going to be like when they get to Baghdad?” a British officer asked.

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