Lebanese government troops have fought heavily armed Sunni Muslim gunmen in the southern city of Sidon, as the war in Syria begins to engulf its smaller neighbour.
At least 16 soldiers were killed and dozens more injured in clashes with militiamen loyal to the outspoken Sunni cleric Sheikh Ahmed al-Assir, in some of the worst fighting in Lebanon since the start of the Syrian civil war.
As dozens of troops advanced in armed personnel carriers, the military appealed to the gunmen to surrender, promising it would "uproot the strife and would not stop its operations until security is totally restored".
The two-year conflict in Syria has reignited sectarian enmities in Lebanon, threatening a return to the bloody days of its 15-year civil war.
Tensions have grown in Sidon, with Sheikh Assir calling for the disarming of the powerful Lebanese Shia militia group Hezbollah.
In a series of media stunts, including the blocking of the highway to Sidon, Sheikh Assir had appeared to position himself as a leader for Lebanon's Sunni Muslims.
Hezbollah's announcement that it was fighting in Syria alongside President Bashar al-Assad, who is also Shia, has brought the embittered relationship with Sunni groups in Lebanon to the brink of war.
Fighters from Hezbollah were reported to have joined the fight against Sheikh Assir.
"Today I am reminded of the atmosphere that brought the civil war in 1975.
"Then I used to hear the sounds of the shelling and of the snipers," said Omar Saad, a Sidon-based politician with the pro-Assad March 8 movement.
The 1975 killing of his father Maarouf Saad ignited the civil war. "This is bitter experience to be repeated. We must deliver this warning to the younger generation," said Mr Saad.
Ed Miliband, Britain's Labour Party leader, will attend a briefing with the National Security Council to discuss Syria today.
The timing of the meeting will add to speculation that the Prime Minister David Cameron is trying to win support from opposition MPs for military intervention in Syria. (© Daily Telegraph, London)