Tens of thousands of people waving Iraqi flags staged a peaceful rally in the southern city of Najaf Monday to demand the withdrawal of US forces, four years to the day after Baghdad fell to invading American troops.

The streets of the Iraqi capital itself were largely empty after authorities clamped a 24-hour ban on vehicles to prevent any insurgent attacks, especially car bombings.

The anniversary comes as Iraq's Shi'ite-led government is trying to avert full-scale civil war between majority Shi'ites and minority Sunnis who were dominant under Saddam Hussein. Sunni and Shi'ite clerics marched side by side in Najaf.

US military spokesman Rear Admiral Mark Fox said that four years ago US-led forces had "liberated Iraq from Saddam's republic of fear". That had allowed Iraqis to exercise their democratic rights and stage protests such as the one in Najaf.

"While there have been substantial accomplishments, the first four years have also been disappointing, frustrating and increasingly dangerous in many parts of Iraq," he said.

The protesters in Najaf were responding to a call by powerful anti-American cleric Moqtada al-Sadr, who blames the March 2003 invasion for the country's woes and wants a timetable set for a US troop withdrawal.

Waving red, white and black Iraqi flags, marchers choked the 7 km long road between Najaf and neighboring Kufa and clogged streets leading to Sadrayn Square, the main rallying point. Many had come from Baghdad and Shi'ite towns and cities in the south.

Sadr has kept out of sight since US and Iraqi forces began a crackdown on violence in Baghdad and was not at the rally. The US military says he is in Iran, but his aides insist he is still in Iraq, possibly Najaf.

Journalists estimated the size of the crowd at tens of thousands, while organizers said the number was far greater. The US military said aerial surveillance pictures showed that 15,000 took part.

Speaking against the backdrop of an Iraqi flag, a senior Sadrist, cleric Abdelhadi al-Mohammadawi, called on US forces to leave. His speech was interrupted by periodic chants of "Leave, leave occupier!" and "No, no, to the occupation".

(China Daily via agencies April 10, 2007)