By DIAA HADID
BEIRUT (AP) - Syrian rebels killed 10 Lebanese troops and likely captured over a dozen more in an ongoing raid on a Lebanese border town, the country's military chief said, the most serious spillover of violence yet into the tiny country from its neighbor's civil war.
The capture raised fears Lebanon could become further entangled in the Syrian civil war and could worsen already-brewing sectarian tensions.
"What happened today is more serious than what some people imagine," Lebanon's army chief, Gen. Jean Kahwaji, told journalists.
The fighting began Saturday as Syrian rebels made a cross-border raid into the eastern Lebanese border town of Arsal, some 90 kilometers (55 miles) from the capital, Beirut. The clashes continued into Sunday, with local television footage showing wailing ambulances racing into town and soldiers standing guard just outside its limits.
The Lebanese military sealed off the area, preventing reporters from approaching the town; the state news agency said fighting Sunday focused around an army barracks in the town's center.
The fate of tens of thousands of residents and Syrian refugees living in Arsal was unclear. Local television stations showed carloads of residents fleeing the area.
Saturday's raid began hours after the army said troops detained Syrian citizen Imad Ahmad Jomaa, who identified himself as a member of the Nusra Front. The state-run National News Agency said Jomaa was detained as he was being brought to a hospital in Lebanon after being wounded while fighting Syrian troops.
The Nusra Front is one of the most powerful groups fighting to overthrow the rule of Syrian President Bashar Assad.
The rebels began the attack by seizing three security compounds in Arsal, Kahwaji said. They were still in control of one compound Sunday, he said.
The army chief said the fighters belonged to extremist Sunni groups, like the Nusra Front. He said the fighting had killed 10 soldiers, while 13 others were missing.
"They may be prisoners of terrorist groups," he said.
A video uploaded to an account associated with the Nusra Front showed over a dozen captured Lebanese soldiers and police officers. In the video, the men announced their defections from the Lebanese army and the Shiite militant group Hezbollah, whose forces are fighting in Syria in support of Assad.
The video of the men's capture appeared authentic and corresponded with Associated Press reporting on the attack in Arsal. But the men appeared uncomfortable as they repeated similar statements as many refused to look at the camera.
Syria's civil war has spilled over into Lebanon on multiple occasions, and inflamed sectarian tensions between Sunnis and Shiites, leaving scores dead. However, previous rebel raids never went so deeply into Lebanese territory. Rebels also directly challenged Lebanese security forces for the first time in their assault on Arsal.
Lebanon's Sunni and Shiite communities have lined up on opposing side of Syria's civil war. Sunnis, including those in Arsal, broadly support the Sunni rebels fighting against Assad. Tens of thousands of Syrian refugees live in and around Arsal and rebels sometimes use the town as a base. Shiites typically back Assad.
Kahwaji said the future security problems caused by Syria's war threatened Lebanon, particularly the existence of extremists among the over 1 million Syrian refugees who have fled into Lebanon.
Syria's conflict began in March 2011 as a popular uprising against Assad's rule, but turned into an insurgency after government forces violently cracked down on demonstrators. It has since become civil war with sectarian overtones. Over 170,000 people, mostly combatants, have been killed in Syria in more than three years of fighting, activists say.