Israel's military on Wednesday offered evidence of what it says is a growing threat from Hezbollah in southern Lebanon, using aerial images to highlight the militants group's activities in towns and villages close to the Israeli border.

In a briefing to journalists, Israel Defense Forces Colonel Ronen Marley revealed previously classified photographs to show what he said was a unit of 90 Hezbollah militants operating in the village of Al-Hiyam, where they were storing weapons close to hospitals and schools.

Open gallery view IDF aerial photo marking alleged Hezbollah strongholds in southern Lebanon, released on July 7, 2010 Credit: IDF

"Hezbollah is establishing itself with increasing strength in the villages," Marley said. "Every day they are collecting significant intelligence on our forces along the border and every day they are engaged in digging, building and laying communications infrastructure to prepare themselves for war."

In the four years since Israel fought a month-long war with Hezbollah, the IDF had collected data on thousand of targets to be bombed by Israel in the event of renewed hostilities, Marley said.

In the last war, much of the fighting took place on open scrubland, he said. But the deployment of United Nations forces in southern Lebanon had forced Hezbollah into built up areas where troops from the international UNIFIL force have no authority.

The IDF believes Hezbollah has an arsenal of some 40,000 short and medium range rockets stored in towns and villages south of the Litani River, with many of the weapons stored in private houses.

Hezbollah also has hundreds of longer range M-600 rockets capable of striking major Israeli cities, Marley said.

The weapons are operated by a force of some 20,000 armed Shi'a Muslim militants, around a third of which have undergone combat training in Iran, available for action at short notice.

Marley said every Shi'a Muslim village had a detachment of between 30 and 200 fighters, whose task would be to hold of the advance of enemy troops into built-up areas in the event of an Israeli invasion.

