Hezbollah's Syrian connections

The big fear, in the Middle East, and beyond, is that Syria's civil war will spill over into neighbouring countries. As the car bomb attack a week ago, which killed a senior security official, illustrated, Lebanon is especially vulnerable.

There has already been fighting in the city of Tripoli, which is close to the border, and as Wyre Davies reports, there is growing evidence that groups which are pro the Syrian government, including Hezbollah, are providing men and weapons to support President Assad's regime.