Western powers and Middle East leaders have joined forces in condemning the assassination of Lebanon's former prime minister Rafik al-Hariri, seen as a major blow for the country 15 years after its civil war.
They hailed the 60-year-old billionaire for masterminding Lebanon's reconstruction from its 1975-90 conflict and expressed concern his death may destabilise Lebanon and the region ahead of the country's general election in May.
"He was a great Arab leader and a Lebanese figure of a very respectable stature," said Arab League Secretary General Amr Moussa, echoing the sentiments of others.
"It's a heinous crime committed against not only Rafik al-Hariri but against Lebanon, against its stability."
UN Secretary-General Kofi Annan said he hoped the assassination would not reignite the civil war.
"It is imperative that the already fragile situation in the region should not be further destabilised," said his spokesman Fred Eckhard.
The White House condemned the murder of a man who "worked tirelessly to rebuild a free, independent and prosperous Lebanon".
A White House spokesman said Lebanon should be able to pursue its future "free from violence and intimidation and free from Syrian occupation", but added it did not know who killed Hariri and was not accusing Syria.
French President Jacques Chirac, a close friend of Hariri, called for an international inquiry into the car bomb attack that killed a person who "personified Lebanon's unshaking will for independence, freedom and democracy."
An unknown Islamist group said it killed Hariri in a suicide attack, calling him a Saudi agent in a video tape aired on Al Jazeera television whose authenticity could not be verified.
Kuwait, Egypt, Jordan, the Palestinian Authority, Britain, Spain and Saudi Arabia all condemned the attack. Jordan's King Abdullah said it was a "cowardly criminal assassination."
Syria, the main power broker in Lebanon but under growing international pressure to withdraw its 14,000 troops, called it an "act of terrorism" aimed at destabilising its smaller neighbour and suggested a link to arch-foe Israel.
"This comes at a time of great international pressure on Lebanon and Syria which aims to realise Israel's desires in the region and this act cannot be separated from these pressures," said Information Minister Mahdi Dahl-Allah.
But Lebanese opposition figures held Syrian and Lebanese authorities responsible for the attack and called for the government's resignation.
Hariri had remained politically influential since his resignation four months ago and recently joined opposition calls for Syrian troops to quit Lebanon in the run-up to the May vote.
Israeli Foreign Minister Silvan Shalom said the attack had killed "one of the most important leaders within Lebanon".
The anti-Israeli Hizbollah guerrilla group, which the United States considers a terrorist group, called it "a heinous crime" aimed at planting strife in Lebanon.