Gemayel, a 34-year-old Christian, was killed Tuesday when two cars blocked his vehicle at an intersection as he left a church and assassins shot him numerous times through a side window.

He was the sixth anti-Syrian figure killed in Lebanon in two years, including former prime minister Rafik Hariri, who was slain in a massive bomb blast in Beirut in February 2005.

Damascus has condemned the assassination and denied any role in it.

The rally, as expected, turned into a display of anti-Syrian feelings among mourners, and many burned pictures of Syria’s president and Lebanon’s pro-Syrian leaders. One man carried a large banner with the pictures of Lebanon’s assassinated leaders and the words: "Syria’s killing regime. Enough!"

Much of the anger was directed at President Emile Lahoud, a staunch Syria supporter, and ralliers held signs calling for his removal. Lahoud was at the presidential palace, where heavy security measures were taken amid fears that protesters would later march there to attempt to force the president to resign.

Anger also was pointed at Hezbollah, which had been calling for mass protests of its own in an effort to topple the Western-backed Prime Minister Fuad Saniora’s government. After Gemayel’s killing, the guerrilla group said it would not hold demonstrations for the time being.

The funeral was expected to revive the 2005 mass protests — the so-called "Cedar Revolution" — after Hariri’s assassination which, along with international pressure, drove Syria to withdraw its army from neighboring Lebanon after nearly three decades of control.

A massive turnout is expected to boost anti-Syrian forces, who are facing heavy pressure from Hezbollah and pro-Syrian groups seeking to unseat the Western-backed government. But it also raised fears it could be the first round of demonstrations that could bring the political standoff into the volatile streets.

While some supporters called for revenge against Syria and its allies, Gemayel’s father — a former president — and the Maronite Church demanded calm, hoping to avert an explosion of violence in the multi-sectarian nation of 4 million.

Though Hezbollah officials said the group would take no action in the coming days to allow emotions to cool, they accused the anti-Syrian parliamentary majority of capitalizing on the murder for political ends to regroup.

"We were on the verge of taking to the streets," said Hussein Khalil, political adviser to Hezbollah leader Sheik Hassan Nasrallah. "The government coalition was in an unenviable position and was in a very big impasse. They needed blood to serve for them as kind of oxygen to give them a new life."

Saad Hariri, son of the slain former prime minister, has urged his mainly Sunni Muslim supporters to take part in the funeral to also rally out of loyalty for the late Hariri and "to renew the celebration of freedom in Lebanon and defend the international tribunal and justice."

It was a major Sunni-Christian coming together, particularly because the Phalange Party fielded the main Christian militia during the 1975-90 civil war between Muslims and Christians in which 150,000 were killed. The move was likely to isolate the Shiites, led by Hezbollah and its ally Amal party, who make up the country’s largest single sect.

 Two Lebanese women cry as they carry a poster of prominent anti-Syrian Christian politician Pierre Gemayel, during his funeral procession, in Beirut, Lebanon, Thursday Nov. 23, 2006. Hundreds of thousands of Lebanese gathered to bid farewell to an assassinated young Christian politician Thursday, and his anti-Syrian allies turned his funeral into a powerful show of force against their opponents, led by the militant Shiite Muslim Hezbollah and its Syrian backers.

 Lebanese mourners wave flags in Martyrs square during the funeral of assassinated Lebanese Industry Minister Pierre Gemayel in Beirut November 23, 2006. REUTERS/Mohamed Azakir

 The coffin of assassinated Lebanese Industry Minister Pierre Gemayel is carried out of a church by supporters in Beirut November 23, 2006. REUTERS/Steve Crisp

 Lebanese mourners carry the coffin of Pierre Gemayel, wrapped in the flag of his Phalange Party during his funeral procession in Beirut, Lebanon Thursday, Nov. 23, 2006. Tens of thousands of Lebanese gathered to bid farewell to an assassinated young Christian politician Thursday, and his anti-Syrian allies turned his funeral into a powerful show of force against opponents led by the militant Shiite Muslim Hezbollah and their Syrian backers.

 Patricia Gemayel, the wife of assassinated Lebanese Industry Minister Pierre Gemayel, cries over his coffin with his brother Samir inside a church in Beirut November 23, 2006. REUTERS/Rafi Barberian