NAJAF, Iraq - Thousands of pilgrims streamed into the Imam Ali Shrine today, and militants who had been holed up in the site left it, handing the keys to Shiite religious authorities after Iraq's top Shiite cleric brokered a peace deal to end three weeks of fighting in this holy city.

Dozens of militants piled Kalashnikov rifles in front of the offices of their leader, radical Shiite cleric Muqtada al-Sadr. Thousands of al-Sadr's militiamen were still believed to be armed in the city, though most were staying off the streets. In one narrow alley, some militiamen could be seen pushing carts full of machine guns and rocket launchers.

Iraqi forces took control of the Old City, which al-Sadr's Mahdi Army militia had used as their stronghold during the fierce fighting with U.S.-Iraqi forces.

Dozens of Iraqi police and national guardsmen deployed around the compound of the walled, golden-domed shrine in the Old City today - but did not enter. Some kissed the compound's gates, others burst into tears. Some residents of the devastated Old City neighborhood waved to them and yelled out, "Welcome. Welcome."

U.S. forces appeared to have maintained their positions in the Old City.

After a day of prayers and celebrations at the shrine - one of Shia Islam's holiest sites - civilians and fighters left, and al-Sadr's followers handed over the keys to the site to religious authorities loyal to Grand Ayatollah Ali al-Sistani, the esteemed cleric who secured the peace deal.

The handover of the keys was a symbolic, yet crucial, step in ending the bloody crisis that has plagued this city since Aug. 5, killing hundreds of Iraqis and nine U.S. troops

, ravaging parts of the Old City and threatening the control of Iraq's interim government

.

Al-Sadr ordered his fighters to lay down their arms and leave Najaf and neighboring Kufa after agreeing to the peace deal in a face-to-face meeting the night before with al-Sistani.

"To all my brothers in Mahdi Army ... you should leave Kufa and Najaf without your weapons, along with the peaceful masses," al-Sadr said in a statement broadcast over the shrine's loudspeakers.

Iraq's interim government also accepted the deal, and U.S. forces ordered their troops to cease fire. Police briefly exchanged fire with militants in one part of town today, and some U.S. troops were still receiving occasional sniper fire. Nevertheless, most of the city was calm.

The agreement leaves the Mahdi Army intact and al-Sadr free, despite U.S. vows in the past to destroy the militia and arrest its leader. Since the transfer of sovereignty June 28, the Iraqi interim government has said it has no intention of arresting al-Sadr, but wants him to turn his militia into a political party.

In the morning, thousands of Shiites marched through Najaf to visit the shrine, which was at the center of the fighting since Aug. 5. Many kissed its doors as they entered, chanting "Thanks to God!"

U.S. soldiers looked on as people passed in the streets, heading to the shrine. Army 1st Lt. Chris Kent said the peace agreement "appears to be a final resolution. That's what it looks like right now."