BEIRUT, Lebanon (AP) – Hundreds of thousands of Lebanese protesters marked the first anniversary of former premier Rafik Hariri’s assassination as anti-Syrian groups called for the resignation of the country’s pro-Syrian president.

Police said 800,000 people turned out Tuesday, waving flags and shouting anti-Syrian slogans in a show of strength aimed at reviving the “people power” spirit that helped break Damascus’ domination. But it remained unclear if they will be able to consolidate control of the government.

So far, the anti-Syrian politicians who are a majority in government and Parliament have been unable to force out President Emile Lahoud or catch culprits in Hariri’s killing or a series of bombings that have killed 11 people, including three prominent anti-Syrian figures.

But the demonstration certainly boosted the sagging morale of anti-Syrian groups, buffeted by the killings and bombings and Syria’s verbal attacks.

The massive crowds filled Beirut’s downtown Martyrs’ Square and mobbed around Hariri’s nearby grave, waving thousands of red-and-white Lebanese flags with the green Cedar symbol.

Women wearing Islamic headscarves joined young women in tight jeans and families, pushing trollies with babies.

Many carried national flags and signs calling for “The Truth,” often shouting the name of Hariri’s son and political heir, Saad Hariri.

Others carried placards denouncing Syria and its president, Bashar Assad.

“Isn’t it enough, Bashar?” said one, listing the names of anti-Syrian Lebanese who have been slain in other bombings in the last year.

The crowds fell into silence at 12:55 p.m. (1055GMT), the time when a huge truck bomb exploded on a downtown street as Hariri’s motorcade drove by a year ago, killing him and 20 others. A horn blew three times to symbolize the instant the bomb exploded. Then the crowd roared with shouts of “Syria out.”

“I came for the sake of national unity,” said Tarek Haj, a nine-year-old Muslim from the northern city of Tripoli.

“Those who killed Hariri meant to kill Lebanon, but they failed. A new united Lebanon was born,” Samia Baroudy, a 52-year-old Christian housewife from a northern suburb, said as she clutched a Lebanese flag.

“We tell them (the Syrians) … remove the symbol of your suppression of Lebanon and its people because the people of Lebanon will not compromise,” Saad Hariri said, referring to Lahoud, drawing chants of “with souls, with blood we redeem you, Saad” from the crowd.

Saad Hariri, who heads the largest parliamentary bloc, returned to Beirut on Sunday, after months of self-exile in Saudi Arabia and France for fear of assassination, to rally the divided anti-Syrian groups for the demonstration. He prayed at his father’s grave before addressing the crowds from behind bulletproof glass.

“There can be no stability and no freedom while the symbol of subservience to the Syrian regime remains in Baabda,” Walid Jumblatt, a major anti-Syrian Druse politician said, referring to the Baabda presidential palace, before he addressed Lahoud. “The terrorist Bashar installed you and the valiant Lebanese people will remove you.”

Neither Lahoud nor Syria had any immediate reaction. Syria has denied any role in Hariri’s killing or the subsequent bombings and has stalled on cooperation in the U.N. probe into the former prime minister’s death.

On Tuesday, U.N. Secretary-General Kofi Annan reaffirmed the U.N. commitment to help Lebanon uncover the truth about Hariri’s assassination and bring his killers to justice, spokesman Stephane Dujarric said in New York.

The United Nations stands with the Lebanese people who “have shown determination to reaffirm the national unity and sovereignty” of Lebanon and to find Hariri’s killers, he said.