The US military said yesterday it would not serve as a police force in Iraq, but some analysts said that was the role American troops must assume to stabilize the chaotic country for months and perhaps years.

The swift collapse of President Saddam Hussein's rule after the US-led invasion has left the impoverished country ravaged by looting and lawlessness.

Analysts said although US soldiers and Marines were not trained to serve as a police force to keep order in a foreign land, by necessity they must do just that to provide security in the face of anarchy.

They said the continuing presence of paramilitary fighters still loyal to Saddam Hussein further complicated an already tough chore.

"As much as US military forces hate to be drawn into policing and providing for public order, absent an international peacekeeping force that is ready to be deployed, we're it," said Michele Flournoy, an analyst with the Centre for Strategic and International Studies.

"The question is whether we're smart enough to step into the breach," added Flournoy, a former Pentagon official.

Looting erupted in shops, government buildings and hospitals in Baghdad and other cities as Saddam's government lost control of power. A prominent cleric hacked to death by a mob in a Shi'ite shrine in Najaf. US troops have been the target of suicide bombings.

"Iraq had lived under a repressive dictatorship for so long that many of the stabilising mechanisms of a civil society are gone. That means that peace will have to be kept at the tip of a gun barrel for some time," said analyst Loren Thompson of the Lexington Institute.

Flournoy said US troops would have to serve in a police role until the United States could reorganise and redeploy Iraqi police and armed forces manned by people not tainted by President Saddam's government. Flournoy said local police forces could be put in place in weeks or months in some parts of southern and northern Iraq less aligned with President Saddam.