Reports of the pre-dawn clashes, which left one US soldier dead, came as a series of loud blasts rang out in Baghdad, waking the city's residents on the first day in more than two decades free of the Iraqi leader's iron-fisted rule.

As mystery continued to swirl around Saddam's fate, the United States relegated him to what US Defense Secretary Donald Rumsfeld called the "pantheon of failed, brutal dictators", but warned that a coalition victory was not yet in hand.

Iraqi loyalist fighters hiding in buildings, under cars, and beneath bridges attacked US Marines along the northern banks of the Tigris river from about 2:00 am (2200 GMT Wednesday), an AFP correspondent on the ground saw.

"There were at least 13 casualties and one soldier killed in action," said US First Sergeant Jeff Treiber, adding that artillery fire could be heard outside the walls of Saddam's Azmiyah palace.

A series of explosions were heard in the capital from 7:30 am (0330 GMT) as planes buzzed overhead, but it was not immediately clear where the blasts had occurred or if coalition planes had caused them, an AFP correspondent reported.

The incidents broke the calm that had reigned over Baghdad since US troops poured into the capital to the cheers of jubilant Iraqis on Wednesday, just three weeks after the US-led war to wrest power from Saddam began on March 20.

The dramatic fall of Baghdad -- symbolized by the toppling of a giant statue of Saddam in the center of the sprawling city of five million people -- capped a blistering three-week US-British military offensive.

To wild cheers and applause, US Marines used a tank recovery vehicle to help a crowd of Iraqis destroy the statue over Al-Fardus (Paradise) Square -- a symbol of the repressive leader's feared, omnipresent rule.

But on Thursday, coalition forces continued to gain control over the city, with Major Pete Farnum saying a mosque on the northern banks of the Tigris -- a suspected Saddam stronghold -- had been secured.

A BBC correspondent said US troops had searched the mosque, where Saddam was rumored to be hiding.

In Washington, US President George W. Bush welcomed the news from Baghdad, allowing himself a brief moment of exultation, saying "They got it down!" when the statue of Saddam fell, but the White House also warned that the war was not over.

"We are still in the midst of a shooting war and men and women are still in harm's way. The war is not over. There remain a lot of dangers ahead," said White House spokesman Ari Fleischer.

US Vice President Dick Cheney cautioned that coalition forces could yet face "hard fighting", while in London, British Prime Minister Tony Blair -- Bush's staunchest ally in the war -- said: "This conflict is not, however, over yet."

Rumsfeld told a Pentagon briefing that Saddam "is now taking his rightful place alongside Hitler, Stalin, Lenin, Ceausescu in the pantheon of failed, brutal dictators, and the Iraqi people are well on their way to freedom."

"Watching them (topple the statue), one cannot help but think of the fall of the Berlin Wall and the collapse of the Iron Curtain," he said.

Rumsfeld again accused Syria of giving military assistance to Iraq, and claimed Damascus had helped members of the Iraqi government escape.

But he warned: "There is a lot of fighting that's left."

And there was still no sign of the weapons of mass destruction that Washington has accused Saddam of possessing -- a claim it used to justify the invasion.

In stark contrast to the stream of defiant declarations from Iraq over the past three weeks, there was not a whisper on Wednesday.

Nothing has been heard from Saddam since a US bomber on Monday obliterated a building in Baghdad where he was believed to be with his two sons.

At the White House, Fleischer said Saddam had "missed his chance" to go peacefully into exile, hinting the administration believed the Iraqi leader was still alive.

"We still don't know his fate," said Fleischer. Russia denied a report that Saddam was sheltering in its Baghdad embassy.

The only remark came from Baghdad's ambassador to the United Nations Mohammed al-Duri, who said "The game is over" -- the first senior official to concede defeat in the US-led war.

"I hope the peace will prevail," al-Douri told CNN, explaining that he had no contact with officials in Iraq. Fox television later reported that al-Duri had boarded a plane for Paris, expected to arrive later Thursday.

But there was no such silence on the streets of Baghdad on Wednesday, where crowds dismissed Saddam with chants of "Traitor!" "Torturer!" "Dictator!"

"We're ecstatic to get rid of him after all these years of war and deprivation," said resident Dinkha Khosina, who rushed to greet US troops.

In Asia, governments cautiously welcomed the fall of Baghdad to US forces, but expressed concern about Saddam's whereabouts and the continued threat of clashes.

"Let's not break open the champagne and celebrate at this stage, there's still a way to go yet," said Australian Foreign Minister Alexander Downer, whose country has contributed troops to the coalition.

In Paris French President Jacques Chirac, who has been one of the strongest opponents of the war, hailed the crumbling of the Hussein regime, and said he hoped the fighting would end soon.

Elsewhere in Iraq, coalition-backed Kurdish forces pushing towards the government-controlled northern oil city of Kirkuk seized the towns of Makhmur and Altun Kubri, a senior Kurdish security source said.

US forces continued to move north towards Tikrit, Saddam's home town which lies 200 kilometers (125 miles) north of Baghdad, a US military spokesman said.

In the southern city of Basra, largely under British control since Monday, British troops were struggling to contain rampant looting, murders and petty crime, but said they hoped to quell the violence in a few days.

The growing anarchy gave urgency to British plans to set up an interim committee drawn from locals to run the city and restore some order.

Iraqi opposition leader Ahmad Chalabi meanwhile complained that the team chosen by the United States to administer post-Saddam Iraq was too slow in arriving.

But Rumsfeld countered that interim administrator Jay Garner, a retired US general, would not move into Baghdad until he and his team could do so safely.

Top aid groups asked the UN Security Council on Wednesday to guarantee their safe passage into Iraq to help those in need of humanitarian assistance, but Rumsfeld said relief supplies were already arriving at Baghdad airport.

The International Committee of the Red Cross temporarily suspended aid deliveries after one of its Canadian workers was killed in crossfire.

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