Israel is searching for Hezbollah’s “Imad 4” missile facility, first revealed by the group in 2024, with Israeli intelligence assessments now focusing on a mountainous belt in southern Lebanon after an operation around Ali al-Taher Heights failed to establish whether the facility had been located.

The search has shifted toward al-Rafi Mount, al-Rihane Mount and Iqlim al-Tuffah, where Israeli surveillance and airstrikes have increasingly concentrated, according to a Lebanese security source familiar with the assessments.

The source told Erem News that Israeli intelligence believes “Imad 4” is the same massive underground facility shown in a Hezbollah video released in August 2024. At the same time, Israeli agencies believe it may be only one component of a much larger network of fortified underground military “cities.”

The network is believed to include entrances and exits, command centers and missile launch platforms that could be distributed across several mountains, with the various facilities operating under the “Imad” name.

According to the source, Israeli agencies are considering two main possibilities for the shift in the focus of operations from Ali al-Taher toward the Rafi-Rihane-Iqlim al-Tuffah area.

Either the Ali al-Taher operation failed to reach the “hard core” of the Imad 4 facility, or intelligence gathered during the operation pointed to deeper extensions of the network farther north.

From Ali al-Taher to al-Rihane

Israel said in September that it had completed the destruction of a large underground complex beneath Ali al-Taher Heights. The Israeli military said the complex contained a network of tunnels, a command center belonging to Hezbollah’s Badr Unit and storage facilities for missiles, drones, anti-tank weapons and explosives.

But the military did not say that the complex it destroyed was Imad 4, despite earlier assessments linking the facility to the area.

About two weeks after the operation ended, Israeli strikes began shifting toward Iqlim al-Tuffah. Both al-Rafi and al-Rihane Mounts were hit in a series of airstrikes, including three documented strikes in the Rafi area and around Sajdah.

The Israeli military said it had targeted a Hezbollah weapons depot in Sajdah.

Open-source information does not provide a complete tally of the strikes on the two mounts during that wave. But available reports indicate a concentrated campaign before information emerged that Israel had asked the Lebanese army to enter al-Rihane Mount and Iqlim al-Tuffah and dismantle Hezbollah facilities there.

The change in the geography of the strikes has fueled speculation that Israel's objective extends beyond individual weapons depots and toward a larger underground infrastructure.

A Network Beneath the Mountains

The Lebanese security source said Israeli intelligence does not view Imad 4 as a conventional tunnel with a single entrance and exit.

Instead, it is believed to be a networked system in which a truck entrance could be located in one mountain, emergency exits or missile launch platforms in another, and command and storage facilities buried beneath the mountain chain connecting them.

That assessment would help explain why Israeli operations have covered a broad mountainous area rather than concentrating exclusively on individual coordinates.

The source said Israel's focus on the Rihane-Rafi-Iqlim al-Tuffah corridor is based on indications collected over several years.

Those include surveillance of heavy vehicles and excavation equipment, possible entrances and ventilation structures hidden in wooded and rugged terrain, as well as analysis of footage released by Hezbollah showing the facility.

If the network is as extensive as Israeli intelligence believes, locating it would require more than identifying a single underground chamber. Investigators would have to trace its entrances, internal routes and different exits to establish the full extent of the complex.

What Is Imad 4?

Hezbollah first revealed Imad 4 in August 2024, releasing footage showing what appeared to be a vast underground tunnel system capable of accommodating large trucks carrying missile launchers.

The video also showed vehicles, personnel and wide passages used for movement and operations, followed by large gates opening from inside the mountain to the outside.

Hezbollah did not disclose the facility's location, and independent parties have not been able to determine where it is.

Its military significance lies in more than missile storage.

The facility appears designed to function as an underground base from which missile systems can be protected, moved and prepared away from aerial surveillance before being transported to launch positions when needed.

The scale of the tunnels could also accommodate logistical facilities and command centers while allowing personnel and equipment to remain protected beneath a thick layer of rock.

That makes finding such a facility potentially far more significant for Israel than destroying a conventional weapons warehouse.

‘Strategic Target’

Retired Brig. Gen. Hisham Jaber said the “Imad” facilities should not be viewed as conventional tunnels but as large military complexes that took years to construct and were excavated deep inside mountains at depths that remain unknown.

Jaber said he believes similar facilities could exist north of the Litani River and in the Bekaa Valley.

He said the complexes were designed to launch long-range missiles from underground and included vehicles and large spaces for moving them, as well as logistical facilities that could allow fighters to remain inside for extended periods.

Their underground design makes them extremely difficult to destroy through airstrikes alone, Jaber said, suggesting that reaching them could require ground operations or air-landings.

The intensity of Israeli strikes on mountainous areas is linked to Israel's belief that facilities of this kind are hidden there, he added.

The Israeli pursuit of Imad 4 also has a broader strategic dimension.

According to the Lebanese security source, Israel believes that gaining control of the mountain belt running through al-Rihane and Iqlim al-Tuffah could eventually enable it to impose the “experimental zones” model under discussion in the wider Lebanon-Israel security process.

Under that concept, the Lebanese army would enter designated areas, dismantle Hezbollah military infrastructure and remove weapons.