Beirut, Lebanon (CNN) -- A U.N. official called Wednesday for stronger international efforts to keep sectarian tensions in Syria from spilling into neighboring Lebanon.
"The situation in Lebanon has become more precarious and the need for continued international support to the government and the Lebanese Armed Forces increasingly important," Jeffrey Feltman, U.N. under-secretary general for political affairs, told the United Nations Security Council during its monthly meeting on the Middle East.
"Tensions over domestic and security concerns remain high throughout the country and are easily exacerbated by developments in Syria," he said.
Feltman urged a clampdown on arms smuggling across the Syrian-Lebanese border, which he said posed a risk to both countries.
Syria's violence has been spilling into Lebanon since May, when a group of Shiite pilgrims was kidnapped in Syria. A series of gun battles, riots and angry protests that month left at least 11 people dead.
Feltman cited the recent spate of kidnappings in Lebanon and Syria by people loyal to the Sunni-dominated rebels and by others aligned with Syrian President Bashar al-Assad, an Alawite Muslim with strong Shiite support.
"In his report to the General Assembly, the secretary-general strongly, strongly condemned kidnapping and retaliatory hostage taking in Syria and Lebanon, and called for an immediate release of all those detained without due process and in violation of their human rights," Feltman said, referring to Ban Ki-moon.
As Feltman spoke in New York, sniper fire more than 5,000 miles away rattled Lebanon's divided city of Tripoli for a third consecutive day.
The bloodshed in Syria has aggravated decades-old animosities between residents of rival areas of Tripoli: the Bab-al-Tibbaneh neighborhood dominated by Sunnis, and the adjacent Jabal Mohsen neighborhood, which is dominated by Alawites.
This week, gun battles in Tripoli have left at least seven people dead and dozens wounded, Lebanese state-run media reported.
Both sides said children playing with BB guns initiated the violence, which somehow escalated into shooting by adult residents armed with guns loaded with real bullets.
In response, the Lebanese army has intervened, seeking to impose order by force.
The violence has raised fears that factional rivalries could erupt into warfare in a country where power is constitutionally balanced among Shiites, Sunnis and Christians.
Syrian troops were deployed in Lebanon between 1976 and 2005, primarily in the north. They were initially called in to help stop a brewing civil war but maintained their significant presence -- which once numbered 40,000 -- long afterward.
Many fear Syria's civil war could threaten the political balance in Lebanon -- one that has managed to prevail since the end of Lebanon's 15-year civil war in 1990.