BEIRUT — Lebanese protesters erected flaming roadblocks and gunmen roamed the streets Saturday in a city on edge after the assassination of a top security official in a powerful car bomb the prime minister linked to the civil war in neighboring Syria.
The crisis raised a terrifying specter for Lebanese who fear their country could easily plunge back into cycles of violence and reprisal that have haunted it for decades.
The explosion Friday in the heart of Beirut’s Christian area killed eight people, including the country’s intelligence chief, Brigadier General Wissam al-Hassan. It was the deadliest bombing in Beirut in four years.
The government declared a national day of mourning for the victims Saturday, but protesters burned tires and set up roadblocks in anger.
Sharbal Abdo, who lives in the neighborhood where the bomb went off, brought his 6-year-old son, Chris, and 12-year-old daughter, Jane, to see the destruction Saturday.
‘‘They were very afraid yesterday,’’ he said. ‘‘They need to face this situation. It may be their future.’’
Lebanese Prime Minister Najib Mikati on Saturday linked the bombing to Hassan’s high-profile investigation this summer that uncovered what authorities called a plot by Syria to provoke chaos in Lebanon with bombings and assassinations.
‘‘I don’t want to prejudge the investigation, but in fact we cannot separate yesterday’s crime from the revelation of the explosions that could have happened,’’ Mikati said.
Mikati, who opponents say is too close to Syria and the Shi’ite militant group Hezbollah, offered to resign after the attack, but was asked by President Michel Suleiman to stay.
Hassan’s inquiry led to the arrest of former Information Minister Michel Samaha, one of Assad’s most loyal allies in Lebanon. Samaha, who is in custody, is accused of plotting attacks in Lebanon at Syria’s behest. Indicted in absentia in the August sweep was Syrian Brigadier General Ali Mamlouk, one of Assad’s highest aides.
Syria has powerful allies here, including Hezbollah, which dominates the government.
For much of the past 30 years, Lebanese have lived under Syrian military and political domination.
Damascus’ hold on Lebanon began to slip in 2005, when former Prime Minister Rafik Hariri was assassinated in truck bomb along Beirut’s Mediterranean waterfront. Syria denied having any role. But broad public outrage in Lebanon forced Syria to withdraw its troops from the country.
The killings of anti-Syrian figures continued for years, however, and Assad has managed to maintain influence in Lebanon through Hezbollah and other allies.
Now, as the Syrian civil war rages just across the border, Lebanon increasingly is being sucked in.
Mikati said Saturday that he had offered to resign after Friday’s car bomb, but said Suleiman asked him not to plunge the country into more uncertainty.
The bombing raised fears that the crisis could unleash Lebanon’s sectarian tensions, a dire scenario for a country that endured a devastating civil war of its own from 1975 to 1990.
The Syrian unrest has already enflamed tensions here. Many of Lebanon’s Sunni Muslims have backed Syria’s mainly Sunni rebels, while Shi’ite Muslims have tended to back Assad.