BAGHDAD — Tens of thousands draped themselves in Iraqi flags and marched peacefully through the streets of two Shiite holy cities yesterday to mark the fourth anniversary of Baghdad’s fall. Demonstrators were flanked by two cordons of police as they called for US forces to leave, shouting “Get out, get out occupier!”Security was tight across Iraq, with a 24-hour ban on all vehicles in Baghdad starting from 5 a.m. yesterday. The government quickly reinstated the day as a holiday, rescinding its weekend order that had decreed that April 9 no longer would be a day off.

The Najaf rally was ordered by Muqtada al-Sadr, the powerful Shiite cleric who a day earlier issued a statement ordering his militiamen to redouble their battle to oust American forces, and argued that Iraq’s army and police should join him in defeating “your archenemy.”

Demonstrators marched from Kufa to neighbouring Najaf, 100 miles south of Baghdad. Those marching were overwhelmingly Shiite but Sunnis, who are believed to make up the heart of Iraq’s insurgency, have also called for an American withdrawal.

Some at the rally waved small Iraqi flags; others hoisted up a giant flag 10 yards long. Leaflets fluttered through the breeze reading: “Yes, Yes to Iraq” and “Yes, Yes to Muqtada. Occupiers should leave Iraq.”

“The enemy that is occupying our country is now targeting the dignity of the Iraqi people,” said lawmaker Nassar al-Rubaie, head of al-Sadr’s bloc in parliament, as he marched. “After four years of occupation, we have hundreds of thousands of people dead and wounded.”

A senior official in al-Sadr’s organisation in Najaf, Salah al-Obaydi, called the rally a “call for liberation.”

“We’re hoping that by next year’s anniversary, we will be an independent and liberated Iraq with full sovereignty,” he said.

Al-Sadr did not attend the demonstration, and has not appeared in public for months. US officials say he left Iraq for neighbouring Iran after the February 14 start of a Baghdad security crackdown, but his followers say he is in Iraq.

Iraqi soldiers in uniform joined the crowd, which was led by at least a dozen turbaned clerics — including one Sunni. Many marchers danced as they moved through the streets.

The demonstration ended without violence after about three hours, but two ambulances could be seen moving slowly with the marching crowd, poised to help if violence or stampedes broke out.

Col. Steven Boylan, a US military spokesman and aide to the commander of all US forces in Iraq, praised the peaceful nature of the demonstration, saying Iraqis “could not have done this four years ago.”

“This is the right to assemble, the right to free speech — they didn’t have that under the former regime,” Boylan said. “This is progress, there’s no two ways about it.”

Yesterday’s demonstration marks four years since US Marines and the Army’s 3rd Infantry Division swept into the Iraqi capital 20 days into the American invasion.

Foreign Minister Hoshyar Zebari said yesterday that “mistakes were made” after Saddam Hussein’s regime was ousted four years ago.

“The main mistake was a vacuum left in the fields of security and politics, and second mistake was how liberating forces became occupation forces,” Zebari told Al-Arabiyah television.

Cars were banned from Najaf for 24 hours starting from 8 p.m. Sunday, said police spokesman Col. Ali Jiryo. Buses idled at all entrances of the city to transport arriving demonstrators or other visitors to the city centre. Najaf residents would be allowed to drive, he said.

Security was tight across Iraq, with a 24-hour ban on all vehicles in Baghdad starting from 5 a.m. Monday. The government quickly reinstated yesterday as a holiday, just a day after it had decreed that April 9 no longer would be a day off.

In a statement distributed in Najaf on Sunday, al-Sadr called on Iraqi forces to stop co-operating with America.

“You, the Iraqi army and police forces, don’t walk alongside the occupiers, because they are your archenemy,” the statement said.

Al-Sadr, who commands an enormous following among Iraq’s majority Shiites and has close allies in the Shiite-dominated government, urged his followers not to attack fellow Iraqis but to turn all their efforts on American forces.

“God has ordered you to be patient in front of your enemy, and unify your efforts against them — not against the sons of Iraq,” it said.

Al-Sadr had reportedly ordered his militia to disarm and stay off the streets during a Baghdad security crackdown that began February 14, though he has nevertheless issued a series of sharp anti-American statements, demanding the immediate withdrawal of US troops.

Sunday’s statement was apparently issued in response to three days of clashes between his Mahdi Army militiamen and US-backed Iraqi troops in Diwaniyah, 80 miles south of Baghdad.

American troops continued operations in Diwaniyah yesterday, detaining four guards at a the office of a Shiite political party and scouring two neighbourhoods in the city’s northern and eastern sections, police said. At least 24 suspects were detained and one civilian was killed, police said. US officials had no immediate comment.

On Sunday, thousands of residents in Baghdad’s largest Shiite slum, Sadr City, boarded buses and minivans bound for Najaf.

Iraqi flags flew from most houses and shops in Sadr City. Drivers and motorcyclists affixed them to their vehicles. Police escorted convoys of pickup trucks overflowing with young boys waving Iraqi flags, en route to Najaf.

Despite the curfews, violence persisted yesterday. In southern Baghdad, a sniper killed a civilian and a policeman, and a mortar round killed one person and wounded two others, police said.