UN chief Ban Ki-moon appeals for calm in Lebanon after gunbattles erupted in the capital, Beirut hoping it wasn't a sign Lebanese sympathies with factions in Syria will break into civil war at home UN chief appeals for calm in Lebanon after fighting erupted between pro- and anti-Syrian groups; Many Sunni in Lebanon's north sympathise with Syria's uprising against Assad say the Lebanese army is taking orders from Damascus UN Secretary-General Ban Ki-moon expressed concern on Monday that violence from the 14-month conflict in Syria could spread to neighbouring Lebanon, and reiterated his fear that the Syrian violence may erupt into a full-scale civil war. In a readout of a meeting between Ban and new French President Francois Hollande on the sidelines of the NATO summit in Chicago, the UN press office wrote that Ban said the world is at "a pivotal moment in the search for a peaceful settlement to the crisis." Ban was "extremely troubled about the risk of an all-out civil war [in Syria] and was concerned about the outbreak of related violence in Lebanon," the UN statement said. At least two people were killed in heavy fighting between rival Sunni Muslim gunmen in Beirut on Monday, medical and security sources said, in the latest violence fuelled by tensions over the uprising against Syrian President Bashar Al-Assad. UN special coordinator for Lebanon Derek Plumbly also voiced concern about the fighting and called on all the parties to stop fighting. "Differences must be addressed through dialogue, not resort to violence," he said in a statement. UN spokesman Farhan Haq told reporters in New York that Plumbly was in contact with all parties in Lebanon's government, which would include the pro-Syrian Shiite Muslim militant movement Hezbollah. Many of Lebanon's Sunni Muslims sympathise with the Sunni-led uprising in Syria against Al-Assad, whose father sent forces into Lebanon during its 1975-1990 civil war. The Syrian army finally pulled out in 2005 under international pressure. But Al-Assad retains powerful allies in Lebanon, including Hezbollah and its pro-Syrian Christian partners in Prime Minister Najib Mikati's government. Peacekeeping force The United Nations has a peacekeeping force in Lebanon in the Hezbollah stronghold south of the Litani River. Asked about a possible redeployment of the force, known as UNIFIL, in light of the recent violence, Haq said it would need to change its UN Security Council mandate to deploy north of the Litani. "We're not looking at that for the time being," he said. The UN Interim Force in Lebanon (UNIFIL) was expanded after the 2006 war between Israel and Hezbollah and now has around 12,000 peacekeepers. Last week, Syria's UN Ambassador Bashar Jaafari sent a letter to Ban and the UN Security Council accusing some Lebanese factions of "incubating" Al Qaeda and the Muslim Brotherhood and helping them to take root along the Syrian border in order to launch attacks on Syria. He also accused Turkey and Libya of arming Syria's opposition, which forces loyal to Al-Assad have tried unsuccessfully for more than a year to crush, killing more than 10,000 people in the process, according to the United Nations. In comments that appeared to bolster the Syrian government's complaints about foreign militants, Ban said last week that he believed al Qaeda was responsible for two suicide car bombs that killed at least 55 people in Syria last week. But the United Nations later said that there was no hard evidence for the charge. Lebanon has had a complicated relationship with Syria, which continues to exercise some influence over its neighbour despite the 2005 departure of thousands of Syrian troops and intelligence operatives from Lebanese soil. The United Nations is deploying up to 300 unarmed military observers to monitor a truce agreed upon in Syria that has yet to take hold.