Hezbollah is preparing "surprises" for the event of an Israeli assault on Iran.

The Hezbollah organization has recently been investing efforts in upgrading its unmanned aerial vehicle (UAV) unit, with the aim of using the UAVs to attack Israel in the event Israel decides to strike Iran's nuclear facilities.

The Hezbollah arsenal includes UAVs — commonly known as drones — of the Ababil ("Swallow") model, developed and manufactured by the Iranian aircraft industry. Iran has developed a number of variants of the Ababil, including a model carrying a warhead packed with several dozen kilograms of explosives. Fears have been voiced in Israel that in the event of war, the Hezbollah will try to launch a large number of drones into Israel's airspace in an attempt to detonate them over targets in the north of the country.

"Hezbollah has been making a special effort to acquire such weapons as part of its offensive lineup against Israel," an Israeli security source says. "As far as they are concerned, it is a sure bet. The Ababil is a relatively cheap weapon and, anyway, the Iranians are supplying Hezbollah with Ababil drones for free. Its operation does not require much training and can be mastered easily. Furthermore, even if it is hit in action, no loss of crew lives is liable to be incurred. Another advantage from Hezbollah's point of view is that the Ababil is a small aircraft that is hard to detect and intercept."

Hezbollah was equipped with the first Ababil drones back in 2002. Since then, the organization launched several of these drones into Israeli airspace, mainly for demonstration purposes. Thus, for instance, in April 2005, Hezbollah launched a reconnaissance model of the Ababil, which managed to penetrate Israeli airspace and return to southern Lebanon — a coup vastly publicized at the time by the organization.

During the Second Lebanon War in 2006, Hezbollah tried using the drones against Israel a number of times. On one of those occasions, August 14, 2006, Hezbollah shot off two Ababil drones, each carrying 40-50 kilograms of explosives, with the intention of bombing strategic targets in Israel. However, the drones were detected in time and an Israeli Air Force (IAF) F-16 was dispatched to intercept them. Performing a complex maneuver, the IAF jet fighter fired a Panther missile which blew up one of the drones in midair, while the other one crashed down, causing no harm. But despite the successful interception, the encounter between the F-16 and the drone demonstrated the difficulty of hitting an aircraft of such small dimensions and low velocity as the Ababil.

According to Israeli Defense Forces sources, the IAF air-defense command, which is equipped with a varied array of means designed to protect Israeli airspace, has been acting in the past two years in coordination with the IAF squadrons to adapt its warfare doctrine to the escalating threats against Israel.