US psychological operations teams, or 'psyops', are distributing the leaflets in various parts of the city.

"Please avoid leaving your homes during the night hours after the evening prayers and before the call for morning prayers," said the message printed in Arabic and English.

"During this time, terrorist forces associated with the former regime of Saddam Hussein, as well as various criminal elements, are known to move through the area and engage in hostile acts," it said.

The leaflet advised people to approach US and British checkpoints cautiously and to avoid carrying anything that might be mistaken for a weapon.

"These are not orders. They say 'please'. It is a sort of stay at home campaign," said Sergeant Richard Belt, a US army public affairs officer.

He said the message sought help to identify 'trouble makers'.

US forces have been seeking to return order to the streets of Baghdad, where looters went on the rampage after the collapse of the Iraqi government.

The leaflet has urged firefighters, medical staff and other civil servants in key services to appear at the Civil Military Operations Centre at the Palestine Hotel in central Baghdad to help restore public utilities.

US forces have begun joint patrols with Iraqi police officers, many of who have put on their uniforms for the first time since American soldiers entered Baghdad. They had stayed home when US forces entered Baghdad fearing being mistaken for combatants.

In the past two days, streets have filled up with people going about their everyday lives although most shops remain closed in the absence of electricity.

But sporadic bursts of gunfire and explosions are still heard, often at night.

The city has been without electricity for many days, but water at ground level is available.