Out in the plain west of the city, marines shepherding a gigantic series of convoys north towards Baghdad have reacted to ragged sniping with an aggressive series of house searches and arrests.

A surgical assistant at the Saddam hospital in Nassiriya, interviewed at a marine check point outside the city, said that on Sunday, half an hour after two dead marines were brought into the hospital, US aircraft dropped what he described as three or four cluster bombs on civilian areas, killing 10 and wounding 200.

Mustafa Mohammed Ali said he understood US forces going straight to Baghdad to get rid of Saddam Hussein, but was outraged that they had attacked his city and killed civilians. "I don't want forces to come into the city. They have an objective, they go straight to the target," he said. "There's no room in the Saddam hospital because of the wounded. It's the only hospital in town. When I saw the dead Americans I cheered in my heart.

"They started bombing Nassiriya on Friday but they didn't bomb civilian areas until yesterday, when these American dead bodies were brought in.

"We know the difference between a missile and a cluster bomb. A missile shoots to one target whereas a cluster bomb spreads after they release it."

Mr Ali said marines now controlled the centre of the city, but that fighting was continuing, with members of Saddam Hussein's Ba'ath party in the forefront.

Asked about the much-vaunted fedayeen militia, reported by some sources to be leading the battle, Mr Ali said: "They are children." Other travellers from Nassiriya said they were press-ganged youths who went into battle dressed in black with black scarves wound around their faces and who fight for fear of the execution committees waiting to shoot them if they try to run.

Watching from behind a barbed wire barrier as hundreds of the marines' ammunition trucks, armoured amphibious vehicles, tankers, tanks and trucks lumbered past through clouds of dust as fine as talcum powder, Mr Ali asked why such a huge army was needed just to catch a sin gle man. "We don't want Saddam, but we don't want them [the Americans] to stay afterwards," he said. "Like they entered into Saudi Arabia, Kuwait and Qatar and didn't leave, they will do here. They are fighting Islam. They're entering under the pretext of targeting Ba'ath, but they won't leave."

Another Iraqi squatting next to him leaned over, pointed to the convoys and said: "This is better than Saddam's government."

The marine convoys, which have been passing northward now almost non-stop for two days, are using a partly-built concrete motorway bridge over the Euphrates which US military engineers have made strong enough to take one tank at a time.

At this point the river is a narrow, slow-flowing blue current. Nassiriya is at the western end of the waterlands once occupied by 200,000 Marsh Arabs, the Ma'dan, whose cul ture, thousands of years old, was all but destroyed by Saddam Hussein with terrible loss of life.

A few yards from the bridge it is possible to sit by the riverbank and watch the green spring reeds which defined the marshes bending in the wind. One of the Ma'dan's high-prowed canoes drifts from side to side on its mooring rope.

But it is not long before the sound of the wildfowl and the lapping water is drowned out by a pair of ash-grey Huey helicopters, chugging low past the palm trees beside the bridge, and the whine of the next tank to cross.

Staff Sergeant Larry Simmons, a Floridian from a marine reconnaissance unit in a foxhole overlooking the bridge, was not impressed by what he saw. "You learn about the Euphrates in geography class, and you get here and you think: 'This is the Euphrates? Looks like a muddy creek to me'."

The marines are aggrieved: aggrieved that the Iraqis aren't more grateful, aggrieved that the Iraqis are shooting at them, aggrieved that the US army's spearhead 3rd Infantry Division tore through Nassiriya earlier in the invasion without making it safe.

"They didn't clear the place, and then they left, and now the marines sure have to clear it," he said. "Just like the goddam army."

And the Iraqis are aggrieved at the marines. A 50-year-old businessman and farmer, Said Yahir, was driving up to the main body of the reconnaissance unit, stationed under the bridge. He wanted to know why the marines had come to his house and taken his son Nathen, his Kalashnikov rifle, and his 3m dinars (about £500).

"What did I do?" he said. "This is your freedom that you're talking about? This is my life savings."

In 1991, in the wake of Iraq's defeat in the first Gulf war, Mr Yahir was one of those who joined the rebellion against Saddam Hussein. His house was shelled by the dictator's artillery. The US refused to intervene and the rebellion was crushed.

"Saddam would have fallen if they had supported us," Mr Yahir said. "I've been so humiliated."

Under the bridge, Sergeant Michael Sprague was unrepentant. The money, the marines said, was probably destined for terrorist activities - buying a suicide bomber, for instance. "The same people we determined were safe yesterday were found with weapons today," he said.

Marine scouts shot two Iraqi men yesterday when they were seen carrying Kalashnikovs. Each man was found to be carrying three magazines, but they never fired at the marines before they were killed.

"They were pointing their weapons in an aggressive manner, and they were taken out," said Sgt Sprague.

Nathen had been captured the previous day, along with dozens of others, and like them, had been let go, Sgt Sprague said. Then they caught him again with a Kalashnikov in mint condition and 3m dinars.

"So the question I would like to be asked is, if this person already went through EPW [enemy prisoner of war] questioning and was found to be OK, why on earth would he come back? The problem with these people is that you can't believe anything they say."

Could he understand the locals' distrust of the US after what happened in 1991?

"If it weren't for the liberal press, we might have taken Baghdad last time," said the sergeant.

In the end the marines let father and son go on their way with gun and money, accepting that both were for personal use. But Sgt Sprague was none too happy to see them go. The convoys have, after all, come under sporadic mortar attack. "There's a mad mortarman out there," he said.

A few miles from the bridge to the south lie the ruins of the ancient city of Ur, founded 8,000 years ago, the birth place of Abraham and a flourishing metropolis at a time when the inhabitants of north-west Europe were still walking round in animal skins.

Sgt Sprague, from White Sulphur Springs in West Virginia, passed it on his way north, but he never knew it was there.

"I've been all the way through this desert from Basra to here and I ain't seen one shopping mall or fast food restaurant," he said. "These people got nothing. Even in a little town like ours of twenty five hundred people you got a McDonald's at one end and a Hardee's at the other."

A few hundred yards downstream, a group of Iraqis, some of them hiding out in the country from the fighting in Nassiriya, invited journalists to strong sweet tea in a farmhouse of whitewashed mud. They spread carpets and cushions on the floor and generously allowed the guests not to take their muddy boots off. Light shone through a triangular window.

Mohsen Ali, a devout Shia fingering amber beads as he spoke, said the Iraqi people would fight for Iraq, if not for President Saddam, although he supported the dictator. The country needed a strong leader, he said - even a brutal one.

"If in Iraq there's a leader who's fair, he'll be killed the next day," he said. "Iraqis have hot blood. If he's not tough, he dies the next day."

http://www.guardian.co.uk/Iraq/0,2759,423009,00.html