It all sounded wearily familiar. On Sunday, at the start of the worst internal violence since the Lebanese Civil War ended in 1990, Saad Al-Hariri, leader of the Sunni Future Movement, gave a press conference.

“Fatah Al-Islam is a terrorist organisation that has been imported into Lebanon. The side that stands behind it is known, and its aims are known,” he said. The message: the hand of Syria is once again stirring trouble to thwart UN efforts to set up a tribunal into the assassination of Lebanon’s former premier and Saad’s father, Rafik Al-Hariri.

Two late-night bombs in the wealthy Beirut shopping and residential areas of Achrafieh and Verdun confirmed such suspicions for many, adding to a litany of alleged Syrian crimes starting before Hariri’s February 2005 killing. A woman was killed in Achrafieh; 10 were injured in Verdun.

The truth may be more complicated. At the time of the arrest of alleged Fatah Al-Islam members in connection with the 13 February twin bus bombings in Ain Alaq, a mainly Christian area north of Beirut, news reports portrayed the group as an archetypal — and Syrian-backed — “rag-tag militia”. But the group that inflicted the army’s worst losses in a single day since the civil war and withstood the ferocious shelling of their base in the northern Palestinian camp of Nahr Al-Bared allegedly numbers as many as 500, suggesting that the government must long have been aware of them.

Street battles erupted at dawn Sunday after Lebanese Internal Security Forces attempted to arrest suspected bank robbers linked to Fatah Al-Islam in Nahr Al-Bared. Gunmen overran army positions, killing many soldiers. The military, forbidden under a 1969 deal from entering Palestinian camps, fought them on the streets, tightening its grip on the camp and shelling it from outside. The bombardment was at best inaccurate, fleeing Palestinians said, destroying homes and at least two mosques along with militant positions.

Little ground support is evident for Fatah Al-Islam among the Lebanese or Palestinians and both, initially, backed army bombardment of Nahr Al-Bared. Palestinian outrage, however, mounted with the civilian death toll. By Wednesday morning, when an uneasy truce was in place allowing exhausted civilians to flee by the thousand, 22 militants and 32 soldiers had been killed, according to Reuters. Dead civilians officially number 27, but with access to Nahr Al-Bared remaining dangerous while many buildings have been reduced to rubble, that toll can only rise.

Fatah Al-Islam splintered from Syrian-backed Fatah Al-Intifada in November, both Damascus and the group deny any link between them. Fatah Al-Islam’s ideology is Al-Qaeda-style Salafism — anti-Shia and anti-US. Experts say most militia members are northern Lebanese, joined by Palestinians, Syrians, Saudis and other Arab nationalities.

A political split between the Sunni-dominated government of Prime Minister Fouad Al-Siniora and the Shia resistance group Hizbullah forms the backdrop to Fatah Al-Islam’s growth, according to Ahmed Moussalli, an expert on Islamist movements at the American University of Beirut.

“In Lebanon in the last few months it seems the Hariri group has been channelling funds and allowing weaponry to enter in order to create a Sunni militia... to bargain with Hizbullah,” Moussalli said. Saad Al-Hariri, Al-Siniora and the rest of Lebanon’s pro-US, anti-Syrian government have stepped up pressure on Hizbullah to disarm.

Moussalli proffers that Fatah Al-Islam, Jund Al-Sham and the larger Usbet Al-Ansar are all affiliated with Al-Qaeda by ideology and because of Iraq. “They found a haven in Lebanon to rest, train and recruit, in particular in north Lebanon, which has always been a hotbed for radical fundamentalists.”

Syria almost certainly facilitated group member movements between Lebanon and Iraq, Moussalli said. “But Syria does not call the shots.” Money from Hariri and the Gulf funded a transformation into Al-Qaeda-style cells. “It started up because of Syrian support, but its rapid growth to a roughly 500-strong force is not due to Syria, it’s due to the Lebanese. And now we have to deal with it,” he said.

Hilal Khashan, professor of political science at the American University of Beirut, concurs, saying that Hariri flirted with militant Sunni groups in northern Lebanon. Soon after coming to power in 2005, he paid $48,000 bail to release four members of the Dinniyeh group, who attempted to establish an Islamic mini-state in the north in 2000. And in February 2006, “the Hariri group bussed many groups in from Akkar,” for a demonstration against the publication of Danish cartoons caricaturing the Prophet Mohamed, “but they went on the rampage, burning the Danish Embassy, a Christian church and a number of stores.” After then, according to Khashan, “Hariri decided to dump them.”

According to Moussalli and other analysts, the visit of US Assistant Secretary of State for Near Eastern Affairs David Welch to Lebanon paved the way for a government crackdown on militant groups Lebanon’s Sunni leaders once nurtured. According to local press reports, Welch specifically asked the government to curb Sunni groups in Lebanon. A US Embassy spokesperson in Lebanon said: “we have expressed our concern about extremist groups in Lebanon.”

Respected US investigative reporter Seymour Hersh warned about government flirtation with Salafi movements in a March report in The New Yorker. He quoted Alastair Crooke — who spent nearly 30 years in Britain’s MI6 intelligence service and now works for Beirut’s Conflicts Forum think-tank — as saying “I was told that within 24 hours [of the group splitting from Fatah Al-Intifada] they were being offered weapons and money by people presenting themselves as representatives of the Lebanese government’s interests — presumably to take on Hizbullah.”

It remains unclear whether this week’s Beirut bombs are linked to the northern fighting. Some believe Hariri — that Syria is trying to block a tribunal — while others blame a third party; Islamists showing solidarity with their comrades under fire or an anti-Syrian party seeking to frame Damascus. As always in Lebanese politics, the truth is obscure.