World leaders and Lebanese politicians have condemned the bomb attack that killed an anti-Syrian Lebanese MP in a mainly Christian suburb of Beirut.
Antoine Ghanim, of the Maronite Phalange party, died with at least six others in the Sin al-Fil district.
US President George W Bush said the killing was "horrific", while a host of Lebanese politicians blamed Syria for the bomb.
Lebanon is poised to choose a successor to pro-Syrian President Emile Lahoud.
Feb 2005: Ex-PM Rafik Hariri
June 2005: Anti-Syria journalist Samir Kassir
June 2005: Ex-Communist leader George Hawi
Dec 2005: Anti-Syria MP Gebran Tueni
Nov 2006: Industry Minister Pierre Gemayel
June 2007: Anti-Syria MP Walid Eido
Sep 2007: Anti-Syria MP Antoine Ghanim
But the country has been mired in an ongoing political crisis, with a deadlock between pro- and anti-Syrian factions in parliament.
Syria denied any involvement with Wednesday's attack, issuing a statement calling it a "criminal act", adding that it undermined hopes for Lebanese national reconciliation.
In Lebanon, many politicians described the attack against Mr Ghanim as a direct attack on the process of choosing a new president.
Lebanese Prime Minister Fuad Siniora called for a UN investigation into the assassination of Mr Ghanim, who had returned to Beirut just a few days before his death to take part in the vote.
Anti-Syrian member of Lebanese parliament
Member of Lebanon's Maronite Christian Phalange party
Elected deputy in 2000
Re-elected in 2005
The killing was "a clear message to silence to voices of freedom and independence", he told the AFP news agency.
Other Lebanese politicians were quick to blame Damascus.
Saad Hariri, son of Rafik Hariri, a former prime minister who was killed in a bomb in 2005, said responsibility lay with Syria.
"I have never seen a more cowardly regime than that of [Syrian President] Bashar Assad's," he told the Associated Press news agency.
Even Mr Lahoud, a pro-Syrian figure, suggested the killing was linked to the upcoming election, saying it was no coincidence someone was killed whenever there were positive developments in Lebanon.
The latest attack has also been criticised by the US, the UK, the EU, France and Italy.
Mr Bush denounced what he described as attempts by Syria and Lebanon to destabilise Lebanon.
"I strongly condemn today's horrific assassination of Lebanese member of parliament Antoine Ghanim," he was quoted as saying by AFP, adding it was part of a "tragic pattern" of attacks.
The bombing was the latest attack on leading figures in Lebanon's anti-Syrian movement, with five others killed since Rafik Hariri's assassination in 2005.
Pierre Gemayel, son of the Phalange leader Amin Gemayel, was shot dead by gunmen in November 2006.
In July 2007, a Muslim member of the movement, Walid Eido, was among at least 10 people killed in an explosion in Beirut's Manara neighbourhood.
Syria has denied any involvement in any of the killings.
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