How did those weapons make it into the camp?

One if by land, two if by sea. It appears that Syria smuggled those arms in over many months using small boats. Here’s Anton Efendi of the excellent Lebanese/Syrian blog Across the Bay:.

I had traced a timeline leading to the clashes, which strongly suggests that this was a planned and timed attack. Yakan’s movement is part of that timeline.

Other reports are also emerging, and awaiting confirmation. The Kuwaiti al-Siyassah claims that the Syrians were giving logistical support to Fateh al-Islam. The first claim is uncertain, and holds that Syrian intelligence were trying to send ammunition and weaponry to the Nahr al-Bared camp by boat (which is how arms were smuggled in the past, either from Ain al-Hilweh or elsewhere) using camouflaged boats.

The other claim is that the Lebanese Army arrested 12 fighters trying to cross from Syria, and that their movement was facilitated by Syrian intelligence. This was the second group to be arrested in recent hours, as the Army had arrested five fighters trying to cross at the same location the day before yesterday.

Also, according to Naharnet, the Lebanese sank a couple of boats full of terrorists trying to flee:

In a related incident, a senior Lebanese military official on Thursday confirmed that troops sank two boats carrying Fatah al-Islam militants as they tried to flee Nahr al-Bared via the Mediterranean sea earlier this week.

The official told Naharnet that all fighters on the boats were killed. He did not give the exact number of dead militants in the attack which took place on Tuesday afternoon.(Naharnet-AP-AFP)

The case against Syrian involvement and instigation of this crisis is circumstantial but compelling. I wrote about it yesterday here.