BEIRUT, Lebanon – The symbols of Syrian power crumbled in parts of Lebanon yesterday as Syrian military intelligence agents emptied their offices in Beirut and Tripoli and workers took down an imposing portrait of Syria’s president in the capital’s seaside boulevard.

Lebanese citizens quickly hoisted their national flag – red and white with a green cedar tree in the middle – outside one of the vacated offices and at the site of the massive Bashar Assad portrait.

The retreat of Syrian intelligence, the arm through which Damascus controlled many aspects of Lebanese life, followed strong demands from America and an anti-Syrian rally Monday that drew an estimated 1 million people – the biggest crowd ever seen in central Beirut.

Premier-designate Omar Karami said he would send emissaries to opposition leaders to try to form a national unity government, but acknowledged it would be difficult. Opposition lawmakers have told Mr. Karami they will not join a Cabinet until all Syrian troops have left Lebanon, Syrian-allied security chiefs have been dismissed and an international inquiry has been appointed into the February 14 assassination of Rafik Hariri, the former prime minister.

President Bush said the Shiite Muslim group Hezbollah could be part of the political mainstream in Lebanon despite its terrorist past.

Mr. Bush spoke after several thousand pro-Syrian demonstrators, shouting “Death to America” and “ambassador get out,” had denounced American interference in Lebanon during a march toward the American Embassy. Lebanese police, troops, and coils of barbed wire stopped the march just over a half-mile from the fortified embassy compound.

“We do not want your false democracy,” said a student speaker in the march, Sobhi Yaghi, which was organized by pro-government student groups.

Syrian intelligence agents packed up their files and furniture at their offices at Ramlet el-Baida on the edge of Beirut. Their goods were loaded into three trucks. In the city’s commercial Hamra district, about two dozen Syrian agents left their office in a car and a van loaded furniture and belongings. They were escorted by Lebanese police.

A short time later, a doorman hoisted two Lebanese flags at the entrance.

The intelligence offices in Beirut were the only remnants of Syria’s military presence in the capital after the withdrawal of troops in 2000. Since then, the headquarters of Syrian military intelligence in Lebanon have been in the town of Anjar, a few miles from the Lebanese-Syrian border.

Syrian military intelligence has been the main instrument of Damascus’s control in Lebanon. Its agents deal directly with the Lebanese, supervising checkpoints, detaining people, and granting permits and licenses. They have even resolved disputes among Lebanese politicians.

In the northern city of Tripoli, men were loading trucks outside the two main offices of Syrian intelligence.

In Beirut, workers removed and folded a giant portrait of Mr. Assad that used to hang on the city’s seafront corniche. About two dozen Lebanese arrived later at the scene waving flags and carried placards that read “the truth” – an opposition demand to unmask information about the assassination of Hariri.