Three deaths show that ethnic tensions are on the rise, reports Lucy Fielder from Tripoli Clashes between the Sunnis and Alawites in two poor neighbourhoods in Tripoli this week killed three people and heightened fears of the dreaded "spill-over" of the Syrian crisis. The fighting erupted at a demonstration against the regime of President Bashar Al-Assad in Bab Al-Tebbaneh, an area hostile to the Syrian leadership since the civil war days. Lebanese army patrols on the border to prevent arms-smuggling and prevent the crossing of armed rebels have also sparked debate this month, since they are widely believed to have come at the Syrian regime's behest. Syria's uprising has reopened the domestic rift concerning relations between the two neighbours, but analysts say the unusual rhetorical restraint showed by usually outspoken politicians suggests no side currently wants to set a match to tinder. Friday's clash was the first of note since last June, when seven people were killed in Tripoli, also following a protest in solidarity with Syria's uprising. This time round, both sides traded rocket-propelled grenades and bullets, then subsequently accusations as to who started it. But tensions had been escalating for several days between Sunni Bab Al-Tebbaneh and neighbouring Jabal Mohsen, home to Lebanon's tiny Alawite community and largely loyal to Al-Assad, their coreligionist. Eventually the army enforced calm, but only after at least 20 people, a number of them soldiers, were injured. Anti-Al-Assad demonstrations have often occurred after Friday prayers in Tripoli in solidarity with those across the border. But the seeds of rancour against the Syrian regime were set much earlier in Bab Al-Tebbaneh, where the pre-Baathist Syrian flag hangs from balconies. More than 600 people were killed in a 1986 massacre in Bab Al-Tebbaneh which residents blame on the regime. "Since then, emotions have been charged and people have been looking for a reason to attack the Alawites," said Hilal Khashan, professor of political science at the American University of Beirut. A fierce assault on the opposition stronghold of Homs may have turned up the heat, since Tripoli is just across the border from Syria's third city. Those tensions exploded frequently at the height of tensions between the anti-regime 14 March movement and the Hizbullah-dominated 8 March alliance, which currently governs Lebanon. Syria had to withdraw from Lebanon, which it had dominated politically and militarily since the civil war ended in the early 1990s, following the assassination of Rafik Al-Hariri on 14 February 2005. The country became polarised between those who blamed Syria for his killing, and Syrian-backed Hizbullah and its allies. A tribunal tasked with trying the suspects indicted four Hizbullah members last year, but the group denies all involvement. Hizbullah's alliance, which also includes Christian Free Patriotic Movement head Michel Aoun, formed a government last June, three months after the Syrian uprising broke out. Najib Mikati, a son of Tripoli and a Sunni like all Lebanese premiers, took the helm and has tried to steer a neutral course on Syria to avoid inflaming tensions or drawing cross-border reprisals. On Sunday, Lebanon expressed reservations on an Arab League plan calling for peacekeepers to be sent in to Syria. Many suspected a message behind the Tripoli clashes, but Khashan saw them as a spontaneous eruption of hostilities. "The fact that they were extinguished pretty quickly shows this wasn't planned at the top," he said. "Tensions in Lebanon will continue as long as the situation in Syria, but they are controlled." Since Lebanon is a mailbox for regional tensions -- a role its larger neighbour risks inheriting as violence escalates -- the relative calm appears to be a sign that regional powers have no interest in seeing the country explode, at least for the moment. Analysts count Lebanon's stability among Al-Assad's security cards, to be played if his regime teeters on the brink of collapse. Saudi Arabia and to a lesser extent the other Gulf countries back the Future Movement of Saad Al-Hariri, son of the assassinated former prime minister and the 14 March bloc he spearheads. "It's in no one's interest to let this get out of control," Khashan said. "Gulf leaders are already worried by the violence in Syria, and the Syrian regime cannot benefit from turmoil in Lebanon, which would only exacerbate that in Syria." Yezid Sayegh, senior associate at the Carnegie Endowment's Middle East Centre in Beirut, also believed Lebanon's politicians were showing restraint. "Both of the main camps are being careful not to go too far because both are aware of the risks," he said. Lebanon experienced civil war from 1975-1990, and many are watching the growth of sectarian tensions with a sense of déj�-vu. Many Christians are apprehensive of the regime falling, like their coreligionists next door, fearing it would be replaced by a hostile Sunni Islamist regime. Iraq's post-war Christian exodus is fresh in their minds. And although Al-Assad's demise would hypothetically weaken his ally Hizbullah and strengthen Al-Hariri, Sayegh said, "we're not heading into an easy transition in Syria, so in reality no one knows how it will go." A growth in Sunni jihadist movements across the border would also benefit few in the Lebanese political mainstream, he said.