Inside Story - Lebanon's rising tensions

Hezbollah has called for a boycott of the UN investigation into the assassination of Rafiq al-Hariri, the late Lebanese prime minister, in 2005. Reports now suggest that some Hezbollah members could be indicted. The Lebanese government has co-operated with the tribunal since it was established but Hezbollah considers the assassination to be an internal matter and has called for a local investigation. Hassan Nasrallah, the Hezbollah leader, believes information from the probe is being passed on to the group's arch rival - Israel. So, has Hezbollah moved on to the offensive? And what role could regional powers play in escalating or defusing rising tensions in Lebanon?