Television pictures showed a car on fire near an amusement park on the crowded seafront road in the western half of the city.
Sixth bomb in month
"The Palestinian refugees are not being treated properly by Lebanon"
Sunny, Ottawa, Canada
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It was the sixth bomb in Beirut
and the surrounding areas over the past four weeks. Two people were killed in the five previous explosions.
The bombs come as the Lebanese army has been locked in battle with Fatah al-Islam fighters in the northern Nahr al-Bared Palestinian refugee camp. At least 144 people have died in the ongoing clashes.
Hashem Ahelbarra, Al Jazeera's correspondent at the scene of the Beirut blast, said: "This is going to be a signal to the Lebanese that those who are carrying out the explosions are tracking people with real intelligence capability and manpower.
"Those who wanted to target [Eido] would have followed him from A to Z and when they saw him leave his car, they would have detonated the bomb.
"Most Lebanese newspapers described Eido as a staunch opponent of the Syrians and a strong ally of Saad al-Hariri."
Al-Hariri is the son of Rafiq al-Hariri, a former prime minister, who was assassinated in Beirut in February 2005. He now leads the Future movement.
|Walid Eido was an outspoken critic of |
Syrian influence on Lebanon [AFP]
After the assassination, al-Hariri addressed the nation, describing Eido as a "martyr".
Walid Eido, who was in his 60s, was a Sunni Muslim member of al-Hariri's the Future Movement, which is part of the March 14 majority bloc.
Eido was a retired judge, who had been critical of Hezbollah and Emile Lahoud, the president, who recently called on Fouad Siniora, the prime minister, to launch an investigation into last year's war with Israel.
Rula Amin, Al Jazeera's correspondent in Beirut, said: "This was an assassination that did not take into account that it could kill civilians as well as those that it had targeted.
Assassinations of anti-Syrians
Walid Eido (June 13, 2007): Sunni Muslim member of al-Hariri's Future Movement
Rafiq al-Hariri (February 14, 2005): Former prime minister
Samir Kassir (June 2, 2005): Journalist and activist
George Hawi (June 21, 2005): Former Communist party leader
Gibran Tueni (December 12, 2005): Newspaper editor and politician
Pierre Gemayel (November 21, 2006): Industry minister and Christian politician
"People did not expect that he would be assassinated in a public street where so many pedestrians would be. This is something that will scare people very much.
"What is significant is that Walid Eido is a member of parliament. In the autumn, the president of Lebanon's term will end, and a new president has to be elected.
"By assassinating Walid Eido the number of members of March 14, who have a tight majority in parliament, has been brought down by one."
"People fear there will be more assassinations in an attempt to undermine the March 14 majority in parliament and to make sure there will be no other president elected who doesn't have the consensus of the whole population, the opposition and pro-government supporters."