Robert Fisk: Syria's slide into civil war seeps across border into Lebanon

Cross-border tank incursions; four Syrian opponents of the Damascus regime kidnapped in Lebanon, supposedly in a vehicle belonging to the Syrian embassy in Beirut; a truckload of ammunition and rocket-propelled grenades destined for President Bashar al-Assad's opponents on the other side of the Lebanese frontier seized by the Lebanese army. Every tragedy has its mystery, I suppose, but this one is taking on Gone With The Wind proportions.

First, the incursions. The Lebanese are a bit sensitive when Bashar's lads appear near their border, apparently looking for gun-runners. And when a Syrian drives a few metres across the frontier and fires a shell into an abandoned factory, it becomes more serious. There have been at least three recorded Syrian incursions into Lebanon and during one of them, a man was killed. The border is notoriously difficult to locate, but opponents of Lebanon's pro-Syrian government raged against this incursion.

They cared a lot less about the lorry-load of weapons on its way to the unofficial border crossing at Wadi Khalek where "armed gangs"(as Assad likes to call those "destablising" the country) were presumably waiting.

On now to the case of 86-year-old Shibli al-Aisamy, a founder of the original Baath Party. He disappeared from his home in the Lebanese mountain town of Aley on 24 May. Then three Syrian brothers from the Jasem family were grabbed by "unknown men" outside a police station in east Beirut when they came to collect their brother, Jasem Merii Jasem, who had been seen handing out flyers calling for "democratic change" in Syria.

Lebanese MPs revealed that, at a parliamentary committee meeting, General Ashraf Rifi, head of Lebanon's Internal Security Force, claimed that Syrian embassy vehicles in Beirut were used in the abductions. Indeed, it appears that some of Rifi's own ISF were driving the cars.

There was the UN this weekend, warning of a "full-blown civil war" in Syria – a distant cousin, I guess, of ordinary civil war – as the death toll in seven months of anti-Assad protests rose to 3,000. On Saturday, the Lebanese press published photographs of a 14-year-old Syrian boy, Ibrahim al-Shaibani, who, it said, had died in a Syrian hospital after being shot in the chest by Syrian security forces. A unit of Syrian army deserters, claiming they were several thousand strong, has now emerged on the internet, along with pictures of some: an audacious act which also proves that the opponents of Assad, while they may not be "gangs", are very definitely armed.