US aircraft have for days been pummelling Iraqi positions in and around Tikrit, Saddam Hussein's home base 160 kilometres (100 miles) north of Baghdad, trying to wear down the remnants of his Republican Guard.

A spokesman for US Central Command in Qatar, Major General Victor Renuart, said Friday that Tikrit was now "an area we're focused on as we continue our military operations."

US reports said intelligence indicated that Saddam may be dead, despite assertions from Washington that there is a lack of evidence either way.

"We have no hard evidence. We have no solid information that he is dead, but it cannot be ruled out," one US official told AFP in Washington.

The top US military commander for Iraq, General Tommy Franks, said Friday that the man who now tops the US most wanted list in Iraq was, along with his regime: "either dead or they are running like hell."

The United States released a list of 52 members of Saddam's regime it says must be killed or captured.

Baghdad and all other major cities besides Tikrit have fallen in rapid succession to the Americans this week as Iraqi forces melted away.

Kirkuk and Mosul, also in the north, were taken Thursday and Friday with the help of Kurdish peshmerga fighters and with little resistance. US special forces them moved in to claim control.

But looting and anarchy have followed the US advance, and hospitals and the UN offices in Baghdad have been stripped clean.

US forces said their first priority would be rooting out remaining resistance but said they had begun patrols in Baghdad on Friday night.

A first group of Iraqi policemen, who have been absent from the streets of the capital since Wednesday, showed up on Saturday and presented themselves to US troops to help restore order.

"We are trying to get the Baghdad police to come back to work and do their jobs and try to maintain civic order," US Colonel Peter Zarcone told the BBC late Friday.

The seizure of Kirkuk and Mosul has unsettled neighbouring Turkey, which fears its own Kurdish minority will again become restless if a de facto Kurdish state dominating Iraq's oil-rich north emerges.

Saturday, Kurdish fighters were withdrawing from Kirkuk in line with an agreement struck between Washington and Ankara to avoid a Turkish invasion in the north.

"The situation is under control," said a senior Kurdish commander, General "Mam" Rostam said. He added that US forces in the major oil city were "more than sufficient" to assure security -- although there were few signs of their presence.

Kirkuk was seized by Kurdish fighters backed by US special forces almost unopposed on Thursday. Hundreds of Kurdish policemen later arrived to try to restore order when the situation began spinning out of control.

The Arabic news channel Al-Jazeera said calm was also gradually returning to Mosul.

Kurdish forces were still present, however, and were seen at major intersections and patrolling roads leading into the city, recovering items that had been pillaged, it reported.

From Mosul's mosques, appeals were going out to police officials of the deposed regime to return to their duties.

Doctors struggling to work in one of only three hospitals still open in the capital were forced to carry rifles, and they were treating looters shot by shopkeepers who had taken law enforcement into their own hands.

The United States is to send nearly 1,200 police consultants, advisors and judicial experts to Iraq in the coming weeks to help establish security in the aftermath of the war, the US State Department said Friday.

Another US commander in the Iraqi capital, Lieutenant Colonel Fred Perdilla, said Friday his forces' priority was rapidly becoming "stabilisation" rather than combat.

"Fighting against a uniform threat or an enemy appears to be winding down, if it's not already over," he said.

Meanwhile, US Central Command announced they had found a dead journalist and two other wounded ones in a Baghdad hospital, as well as a fourth who was uninjured.

They did not give further details on the identities of the four.

In Basra, British troops have stepped up their presence in the country's second-largest city in a bid to restore calm following several days of looting and chaos there, a British military spokesman said Friday.

"Our priority in Basra is to make the city secure so the United Nations can get in there. We have increased our presence in the streets," said Group Captain Al Lockwood.

SPACE.WIRE