The Iraqi strongman, dressed in the military garb he has worn since the war began, was seen on state television in a huddle with top military and political brass including his son Qussay, head of the elite Republican Guard.

Saddam has stepped up his appearances on television in recent days and even taken a well-publicized walk on the capital's streets to counter the mounting impression that his grip on power is slipping.

But it was not clear when or where the meeting took place.

Meanwhile, huge explosions boomed out and thick smoke filled the sky over the main Republican Palace, a key symbol of Saddam's power, as US forces launched a raid into the sprawling riverside compound in the heart of Baghdad.

AFP reporters saw 10 US marines in full combat gear and armoured vehicles inside the palace, which has been pounded repeatedly since the US-led coalition launched the war 19 days ago.

US troops met with fierce resistance at the compound where dozens of black-clad Iraqi elite troops were seen running along a bank and entering one of the main buildings.

Amid heavy exchanges of mortar and rocket-propelled grenade fire, clouds of smoke covered the 2.5-square kilometre (one-square mile) palace, which houses Saddam's personal office and an underground bunker designed to withstand nuclear attack.

Lieutenant Colonel Peter Bayer, operations officer for the US army's 3rd Infantry Division, said US troops had "secured the main presidential palace" and another palace in the city center as well as a third near the airport.

But Iraq insisted it was still in control, with Information Minister Mohammed Said al-Sahhaf assuring reporters the invaders would be "massacred".

"They pushed forward some troop transporters and tanks, we have surrounded them with our troops," Sahhaf said.

"We will massacre them, these invaders. Their graves will be here."

AFP correspondents said the administrative district around the palace, including the ministries of information and foreign affairs, were still in Iraqi hands.

Warplanes roared low over Baghdad during the afternoon. Iraqi anti-aircraft defenses opened fire despite minimal visibility due to the smoke and dust covering the city.

In the late afternoon, a missile crashed into a residential neighborhood in central Baghdad killing at least nine civilians, witnesses said.

A building collapsed and several others were damaged on Ramadan 14th, a main commercial artery in the al-Mansur area.

Fighting intensified in the afternoon at the palace compound, where at least three Bradley fighting vehicles fired on the buildings on the banks of the Tigris.

Troops got out of one of the vehicles and entered one of the buildings after setting fire to surrounding bushes.

The troops then blew up a nearby building.

Clashes also erupted around Baghdad's landmark al-Rashid hotel, which had been cordoned off by Iraqi fighters, AFP correspondents said.

Iraqi paramilitary fighters were seen firing assault rifles and rocket-propelled grenades from different angles toward the area of the al-Rashid, they said.

It was not clear who was returning fire. There were no immediate reports of casualties.

Clusters of men in both military fatigues and civilian clothing, ammunition strapped across their chests, stationed themselves behind sandbags, walls and trees along the roads, as military jeeps on street corners kept their mounted anti-aircraft guns pointed horizontally.

The western Al-Karkh bank of the Tigris -- home to Saddam's presidential compound and government ministries -- was deserted except for a crowd of hundreds of civilians at the gate of Al-Alawi bus station.

"All these people came here because they wanted to leave town, but there are no buses," said a doctor from Al-Rashid military hospital trying to travel to his home in Al-Faluja, 30 kilometers (20 miles) west of Baghdad.

The civilians tried to flag down the odd passing private car in the hope of hitching a ride home or out of the besieged city.

"I didn't know there was an attack. I was caught up in the battle," said the doctor, explaining he had just come off a night shift.

"Eighty percent of the hospital beds are taken by people suffering from war injuries," he said.

On the eastern Al-Rusafa bank of the Tigris, traffic was also slow but small neighborhood cafes were still full of people, grocers' stores open, fruit stalls erected and street vendors hawking cigarettes stood on main roundabouts.

Civilians trying to drive on Al-Jumhuriya bridge over the Tigris, close to the palace compound, were stopped by armed militiamen who did, however, allow military vehicles to cross.

SPACE.WIRE