Israel's Mossad spy agency planted a small amount of explosives inside 5,000 Taiwan-made pagers ordered by Lebanese group Hezbollah months before Tuesday's detonations, a senior Lebanese security source and another source told Reuters.

Israel's military announced that it had struck more than 100 Hezbollah rocket launchers and infrastructure sites in southern Lebanon, in what security sources described as one of the largest assaults since the conflict reignited last October.

A series of explosive pager blasts in Lebanon killed at least nine people and injured nearly 3,000. The coordinated attack was part of an Israeli operation targeting Hezbollah members. The pagers were made by a Hungarian shell company and imported from Taiwan.