Hundreds of thousands of people packed into central Beirut on Tuesday, waving red and white flags and pictures of the slain prime minister who was credited with rebuilding their country after the devastating civil war.

Arriving at Freedom Square by bus, car or on foot, demonstrators chanted "No, no to the mukhabarat" in reference to the once-feared Syrian secret police, as loudspeakers played patriotic songs and Quranic verses. The rally was called by the anti-Syrian coalition led by al-Hariri's son and political heir, Saad al-Hariri, who says that those behind the killing should be brought to justice.

Other victims

Demonstrators also carried pictures of other Lebanese politicians and journalists targeted in bombings over the last year. The city centre was closed off to traffic against a background of a massive security deployment for the anniversary of an event that plunged Lebanon into turmoil and changed its political landscape.

Al-Hariri and 20 others perished in a massive car-bomb blast

Al-Hariri's son Saad had returned home at the weekend after six months in exile to issue an appeal for a massive turnout.

Saad, now the head of the anti-Syrian majority in parliament, said: "I call on all Lebanese to adopt a historic position of unity on this day to show that our national unity is above all else and that the forces of 14 March will remain united."

Saad said in an interview with Lebanese television: "We do not ask for a change of regime in Syria, but that it makes peace. We thank Syria for having ended the war in Lebanon but we will handle our own affairs now.

"The Syrian regime did a lot of wrong in Lebanon and spared her neither insults nor threats."

Continuing divisions

However, in a sign of continuing divisions in Lebanon, the pro-Syrian Shia movement Hizb Allah and a major Christian leader, General Michel Aoun, have refused to endorse the commemoration, charging that it had been "politicised".

Jumblatt: Every Lebanese is invited to pay homage to al-Hariri

"Every Lebanese is invited to pay homage to Rafiq al-Hariri on Tuesday by placing a rose at the site of the attack or at his tomb," said Druze leader Walid Jumblatt, an anti-Syrian MP.

Thousands of Lebanese soldiers and police were deployed in Beirut and its suburbs, as people converged on Martyrs' Square in downtown Beirut on Tuesday, where al-Hariri is buried.

The rally, described as a "gathering of loyalty and national unity", climaxed shortly after midday, the time when a huge truck bomb exploded on a downtown seaside street as al-Hariri's motorcade drove by, killing him and 20 others.

Security tight

A Beirut billboard carrying the picture of the slain ex-premier

 "We miss you," read large posters with a smiling al-Hariri.

"They feared you, so they killed you," others said.

Many in Lebanon say Syria was behind the killing of al-Hariri.

An ongoing UN inquiry has implicated senior Syrian security officials and their Lebanese allies.

Damascus denies any role.

Four pro-Syrian Lebanese generals have been detained and charged with roles in the murder, but no indictments have yet been issued.

Chirac's message

Chirac (R) says he will ensure the guilty are punished

One of his personal friends was Jacques Chirac, the French president and the driving force behind several UN Security Council resolutions on Lebanon and the al-Hariri investigation.

Chirac told Future Television on the eve of the anniversary: "I can tell you that the international community's determination to find and punish the guilty, on the one hand, and to give Lebanon all the means for independence, security, democracy and freedom, on the other hand, has not moved at all."

But despite the Syrian pullout in April, a string of bombings and the assassination of three anti-Syrian figures as well as a series of political crises and the resurfacing of sectarian tensions, have raised fears that Lebanon could slide into instability.