Throwing rose petals and waving red, white and green Lebanese flags, hundreds of mourners lined the streets of Beirut Saturday for the funeral procession of an anti-Syrian journalist amid calls for an international investigation into his death.

Samir Kassir (search), a 45-year-old newspaper columnist, was killed Thursday by a bomb that exploded under his car in the Christian Beirut neighborhood of Ashrafieh (search). Lebanon's opposition blamed Syria for the assassination — a charge Syria strongly denied — and accused Damascus of continuing to interfere in Lebanese politics.

Kassir was laid to rest Saturday in St. Mitr Cemetery, a few hundred yards from where he died. More than 2,000 people watched as his coffin was carried from the offices of his newspaper, An-Nahar, in downtown Martyrs' Square (search), by pallbearers including the newspaper's director-general, Gibran Tueini.

Mourners threw rose petals on the coffin as it made its way to nearby St. George's Greek Orthodox church (search).

The funeral was attended by several opposition leaders including Walid Jumblatt, Amin Gemayel and Saad Hariri, son and heir of former Prime Minister Rafik Hariri, who was killed by a huge car bomb in Beirut on Feb. 14. The Lebanese opposition had asked government officials not to attend the funeral.

Kassir's wife, Giselle Khoury, and daughters Layan and Maysa wept in front of his coffin during the funeral Mass. Khoury, a journalist with Al-Arabiya television, demanded an international investigation into the death of her husband, who held French and Lebanese citizenship.

"His pen will be the pen that we will continue to write with," said Nayla Tueini, an An-Nahar journalist and daughter of the daily's director-general. "Our mission is to follow Samir's path."

After the funeral prayers, young members of Kassir's Democratic Left Movement carried the coffin outside the church chanting "Samir, we are your dream." Hundreds of people marched behind the coffin as it was carried to the cemetery for burial.

Lebanon's anti-Syrian opposition, which has demanded for months that pro-Syrian President Emile Lahoud resign, called for demonstrators to gather near the presidential palace on Monday.

Lahoud has condemned the killing of Kassir, but the opposition was unimpressed.

Opposition leader Elias Atallah (search) said protesters would lay a wreath "that clearly points to the direct responsibility of this security regime."

Syria pulled all its troops out of Lebanon in April after three decades, and Lebanon is in the midst of parliamentary elections that the opposition hopes will end Damascus' control of the legislature.

The second of four rounds of voting will take place Sunday in southern Lebanon.

European legislators Jose Ignacio Salafranca and Carlos Carnero, both members of a European mission to monitor Lebanon's elections, strongly condemned Kassir's killing, calling it an attack against the freedom of speech of the Lebanese people.

Justice Minister Khaled Kabbani on Saturday appointed judge Sami Sidki to investigate Kassir's killing, but there is widespread skepticism in Lebanon about the state's ability to investigate political crimes.

The White House said Friday it wants the United Nations to expand its inquiry into Rafik Hariri's killing to include the death of Kassir.

FBI agents already are assisting Lebanon's investigation into Kassir's assassination, Lebanese Justice Ministry officials said. Five French investigators arrived in Beirut Saturday to assist with the inquiry.

Meanwhile, Sen. Tom Coburn (search), R-Okla., met Saturday with Lahoud and Saad Hariri. Coburn expressed the United States' readiness to help Lebanon in various fields, Hariri's office said in a statement.