The Israeli military has launched an unprecedented operation to discover and neutralize Hezbollah’s cross-border attack tunnels, apparently taking Hezbollah by surprise. While the operation is unlikely to trigger a new war, it could raise tensions along the volatile border – and with no guarantees that the Israelis will find all the tunnels, writes Nicholas Blanford


The Israeli effort to uncover Hezbollah’s alleged cross-border attack tunnels appears to have taken the Iran-backed party by surprise given its, so far, low-key response to an unprecedented – and potentially embarrassing – operation that seems to have confirmed one of Hezbollah’s key offensive tactics in the event of another war.

Hezbollah has yet to make a formal announcement on Israel’s so-called Operation Northern Shield. For now, Hezbollah has been needling the Israelis by publishing numerous close-up photographs of Israeli soldiers involved in the survey work along the Blue Line, the UN’s name for the border. Local residents have been encouraged to gather at some of the more accessible sites, such as opposite Kfar Kila and Blida villages, to vocally mock Israeli troops or hold picnics in a gesture of nonchalance toward the Israeli activities. However, if the operation continues for weeks or even months, as the Israeli military has suggested, the chances of friction developing along the border – by accident or design – will increase.

“Deterrence will only work when one side understands the capabilities at the disposal of the other side”

Hezbollah justifies its retention of weapons as a defense against future Israeli aggression. While surface-to-surface rockets and missiles are, by nature, offensive weapons, Hezbollah’s substantial arsenal is intended first and foremost, the party’s leaders say, to deter Israel from attacking Hezbollah or Lebanon. Deterrence will only work when one side understands the capabilities at the disposal of the other side. Israel may not know exactly how many missiles Hezbollah possesses (although it frequently releases guestimates in the media) but it knows that Hezbollah has sufficient numbers and varieties to wreak unprecedented damage on the Israeli home front – hence the deterrence. The cross-border tunnels, however, had no intrinsic deterrence value because they remained unknown, albeit long suspected, until Israeli troops began uncovering them a week ago.

Furthermore, tunnels dug into Israel serve an offensive, not defensive, purpose. They are intended to allow relatively large numbers of fighters to slip undetected into Israel in a time of war to carry out sabotage missions, seize border communities and generally cause havoc in northern Israel, forcing the Israeli military to fight on its own soil, a reversal of traditional Israeli doctrine to wage wars on the territory of its enemies.

From shortly after the 2006 war, Hezbollah fighters were hinting to this writer that they were being trained to seize and hold ground, contrary to the party’s traditional hit-and-run tactics, and that in the next war they would be crossing the border into Israel. Sheikh Hassan Nasrallah, Hezbollah’s secretary-general, referred to this new tactic in a speech in 2011 when he said that in the next war he might “ask the resistance to liberate Galilee”.

The Israelis have taken the threat seriously and in the past two years have beefed up the physical defenses along the border to impede future infiltrations. Now, they are looking to block Hezbollah’s subterranean conduits.

Since the operation began in early December, the Israelis have announced the discovery of three tunnels crossing into Israeli territory. According to security sources in south Lebanon, two of the tunnels lie southwest of Metulla and may be part of the same network. The location of the third tunnel is unclear as the Israelis have not revealed its whereabouts at present.

On December 10, Hezbollah released a map of the ongoing Israeli tunnel searches, identifying five locations – Metulla (opposite Kfar Kila), east of Meiss al Jabal, east of Blida, south of Ramieh and south of Labboune. The sources said that drills have been spotted at the Blida, Meiss al Jabal and Ramieh locations and are being used to bore through the limestone bedrock in an attempt to expose the tunnels. While the drills are testing different spots in close proximity near Meiss al Jabal and Blida, the Ramieh drill has remained still, suggesting that the third undisclosed tunnel is in fact opposite Ramieh. Residents of the Israeli settlement of Zarit, opposite Ramieh, have long complained about subterranean noises beneath their homes, making this section of the border a top priority in the hunt for tunnels

This picture taken on December 4, 2018, near the northern Israeli town of Misgav Am, shows Israeli operating machinery (R) near the border wall with Lebanon after Israel’s army said it had detected Hezbollah “attack tunnels” in Israeli territory (Jalaa Marey/AFP)

Some Israeli media have quoted military sources as stating that a Hezbollah mole passed on the information on the whereabouts of the attack tunnels. A more likely explanation for the discovery of the three tunnels so far is the use of ground-penetrating technology such as electrical resistivity tomography or seismic tomography which use electrical currents and sound waves respectively to map sub-surface structures. The Israelis also seem to have been employing sensitive listening devices to detect sounds of digging. The Israeli military has released an audio recording of what it says was underground drilling by Hezbollah.

While Hezbollah has remained silent on the tunnels, the Lebanese media has quoted numerous sources playing down the impact of the Israeli search, describing the tunnels as “old” or in one article accusing the Israelis of having dug a tunnel itself. Al Markazia news agency quoted a security source on December 13 as claiming that the first tunnel discovered by the Israelis (and confirmed by UNIFIL peacekeepers) was in fact dug by the Popular Front for the Liberation of Palestine-General Command and used to store weapons and fire rockets into Israel in 1980. The PFLP-GC did construct numerous tunnel networks in south Lebanon in the 1970s and their remnants can still be seen in Sarafand on the coast and outside Arab Salim near Nabatieh. But the PFLP-GC’s trademark tunnels were large enough to house trucks and artillery. Their locations were well known and impossible to disguise. The still active PFLP-GC base at Naameh south of Beirut has been a repeated target of Israeli airstrikes over the years, the last one in August 2013.

“The tunnel at Metulla, on the other hand, bears the hallmarks of Hezbollah which has employed subterranean facilities since the mid-1980s”

The tunnel at Metulla, on the other hand, bears the hallmarks of Hezbollah which has employed subterranean facilities since the mid-1980s. Unlike the PFLP-GC’s large-scale and visible tunnel systems, Hezbollah opted for small, man-sized and cunningly-camouflaged bunker and tunnel networks for storing weapons and ammunition, protecting against Israeli artillery and air strikes and carrying out ambushes. Anyone who wants to know what Hezbollah’s tunnels look like need only visit the party’s resistance museum on the Mlita hillside near Ain Boussoir village. Since 2010, when Hezbollah opened the museum, thousands of tourists have traipsed through a dank, narrow steel plate-lined tunnel that was built after 1985 and serves as the prototype for a network of underground facilities that the Iran-backed party dug in the south Lebanon border district between 2000 and the outbreak of war in 2006.

This writer explored two abandoned Hezbollah bunkers in 2007. The larger of the two was located about two kilometers from the border halfway up the side of a wadi covered in dense undergrowth. It consisted of the same steel plate-lined corridor as the tunnel at Mlita, running some 40 meters in length and interspersed with thick steel blast doors. It had a bathroom with a hot water boiler, sleeping quarters and a kitchen with hot and cold running water and pipes running along the ceiling carrying electricity cables and water. The facility was accessed by horizontal and vertical shafts. The interior was painted glossy white to reflect the electric lighting, while the entrances were painted matt black to prevent stray sunbeams from alerting overhead Israeli aircraft on reconnaissance missions. On a subsequent visit in 2008, the interior fittings – such as latrine and kitchen sinks – had been stripped out and the white walls were spotted with brown rust. By 2012, the tunnel was home to a colony of bats.

The quarried rock spoil from this one bunker alone must have amounted to thousands of tonnes but from the outside there was no evidence that any digging had occurred. All the spoil had been scattered by hand beneath the dense canopy of trees on the hillside, hiding any evidence of digging from Israeli jets and reconnaissance drones that prowled Lebanese airspace on a near-daily basis.

“Hezbollah is thought to have constructed more than 1,000 underground facilities in Lebanon’s southern border district up to 2006”

Hezbollah is thought to have constructed more than 1,000 underground facilities in Lebanon’s southern border district up to 2006, some of them adjacent to the frontier itself. One extraordinary example of Hezbollah’s covert underground activities was the construction of a large bunker at Labboune, the site of a long-abandoned farm on a hill above the coastal village of Naqoura, home to UNIFIL’s headquarters.

The bunker was discovered by Israeli troops in the days after the August 14 ceasefire that ended the 2006 war. It ran to a depth of 40 meters and consisted of dormitories, kitchens, ammunition storage, medical facilities and was large enough to house dozens of fighters for weeks. The Israelis dynamited the facility and the next day this writer visited Labboune with an Italian colleague to see what remained. All that was left of the bunker was churned earth and slabs of meter-thick reinforced concrete poking out of the ground. But the jaw-dropping surprise was that it was built a mere 100 meters from a UN observation post on the border, 500 meters from a UNIFIL position and 800 meters from Israel’s largest military compound on the border – all three facilities within eyeshot of the bunker location. Furthermore, it was built directly beneath an old Israeli minefield. Asked how it was possible for Hezbollah to build such an elaborate underground facility screened only by some bushes and oak trees without anyone seeing, a UNIFIL officer replied “We never saw them build anything. They must have brought the cement by the spoonful”.

If Hezbollah was able to construct such elaborate underground facilities so close to the Blue Line, little wonder that the organization has tunneled beneath the border.

The Israelis say they expect the operation to take weeks, possibly months, to uncover Hezbollah’s tunnels. But there will always be a nagging uncertainty in Israel as to whether they will actually have been able to detect and neutralize them all.

Nicholas Blanford is a veteran Beirut-based correspondent and Nonresident Senior Fellow at the Brent Scowcroft Center of International Security at the Atlantic Council