Hezbollah's flexible chain of command, along with an extensive network of tunnels and a huge arsenal of rockets and weapons it has beefed up over the past year, is helping it withstand unprecedented Israeli attacks, three sources familiar with the Lebanese militant group's operations told Reuters.
Israel's attack on Hezbollah over the past week, including the targeting of senior commanders and the detonation of explosives in pagers and walkie-talkies, has sent Lebanon's powerful Shiite militant group and political party into a state of shock.
Last Friday, Israel killed the commander who founded and led the group's elite Radvan unit, Ibrahim Akil. And since Monday, the bloodiest day of violence in Lebanon in the last few decades, according to the Ministry of Health, over 600 people have died, including at least 50 children.
Israeli Chief of Staff Herzi Halevi said on Sunday that Akil's death had shaken the organization. Israel claims that its strikes also destroyed thousands of Hezbollah rockets and shells.
Halevi told troops on Wednesday that airstrikes in Lebanon would continue to destroy Hezbollah infrastructure and pave the way for a possible ground operation by Israeli forces.
"You can hear the planes above us, we are striking all day," General Halevi told the soldiers on the border with Lebanon. So let's prepare the ground for your possible entry in order to continue weakening Hezbollah," he said.
But two sources familiar with Hezbollah's operations said the group quickly named replacements for Akil and other senior commanders killed last Friday in an airstrike in Beirut's southern suburbs. Hezbollah leader Said Hassan Nasrallah said in a speech on August 1 that the group is quickly filling gaps after the killing of a leader.
A fourth Reuters source, a Hezbollah official, said the attack on communications equipment disabled 1.500 fighters due to their injuries, with many blinded or left without arms in the blasts.
While that's a serious blow, it's only a fraction of Hezbollah's strength, which a recent US Congressional report estimated has between 40.000 and 50.000 fighters. Nasrallah claims the group has 100.000 fighters.
Since October, when Hezbollah opened fire on Israel in support of its ally Hamas in Gaza, the group has redeployed fighters to the front lines in the south, including some from Syria, three British agency sources said.
It has also accelerated the acquisition of missiles, anticipating a protracted conflict, the sources added, noting that the group is seeking to avoid all-out war.
The main supporter and supplier of weapons to Hezbollah is Iran. The group is the most powerful faction in Tehran's “axis of resistance,” which includes irregular forces across the Middle East. Most of their weapons are Iranian, Russian or Chinese models.
The sources, who asked to remain anonymous due to the sensitivity of the subject, did not provide details about the weapon or where it was purchased.
Hezbollah's public relations office did not respond to Reuters' requests for comment.
Andreas Krig, a senior lecturer at King's College London's School of Security Studies, said last week's attacks had disrupted Hezbollah's operations, but that the group's networked organizational structure helped make it an extremely resilient force. "This is the most formidable enemy Israel has ever faced on the battlefield, not in terms of numbers and technology, but in terms of resilience."
Powerful rockets
Clashes escalated last week. Israel killed another senior Hezbollah commander, Ibrahim Kubaisi, on Tuesday. For its part, Hezbollah has shown the ability to continue operations, firing hundreds of rockets at Israel in ever-deepening attacks.
On Wednesday, Hezbollah said it targeted the headquarters of Israel's Mossad intelligence agency near Tel Aviv, more than 100 kilometers from the border. Alarm sirens sounded in Tel Aviv as a surface-to-surface missile was intercepted by air defense systems, the Israeli military said.
Hezbollah did not say whether it had launched any of its most powerful, precision-guided missiles, such as the Fateh-110, an Iranian ballistic missile with a range of 250-300 kilometers. Hezbollah's "Fateh-110" missiles carry a 450-500 kilogram warhead, according to a 2018 report published by the Center for Strategic and International Studies in Washington.
Hezbollah's rocket attacks were possible because the chain of command continued to function despite the group being thrown into chaos following the detonations of pagers and walkie-talkies, a senior security official said.
The three sources said Hezbollah's ability to communicate is aided by a landline telephone network - which they describe as critical to communication and continued operations - as well as other devices. Many of the fighters, for example, were carrying older models of pagers that were not affected in last Sunday's attacks. Most of those injured by explosive devices were in Beirut, far from the front.
This is the most formidable enemy Israel has ever faced on the battlefield, not in terms of numbers and technology, but in terms of resilience, Krieg said.
Hezbollah has stepped up its use of pagers after banning its fighters from using cellphones on the battlefield in February in response to the killing of commanders in attacks.
If the chain of command is broken, frontline fighters are trained to operate in small, independent formations stationed in villages near the border, capable of fighting Israeli forces for extended periods, the senior source added.
This is exactly what happened in 2006, during the last war between Hezbollah and Israel, when fighters of this group held out for weeks, some of them in villages on the front lines occupied by Israel.
Israel says it escalated the attacks to weaken Hezbollah's capabilities and allow tens of thousands of displaced Israelis to return to their homes near the border with Lebanon, where they fled when Hezbollah began firing rockets on October 8.
Prime Minister Benjamin Netanyahu's government has said it prefers a negotiated deal, which would see Hezbollah withdraw from the border region, but is prepared to continue the bombing campaign if Hezbollah refuses, without ruling out any military option.
Hezbollah's resilience is raising fears of a protracted war that could draw in the United States, Israel's close ally, and Iran — especially if Israel launches a ground offensive in southern Lebanon and becomes mired in the conflict. The Israeli military did not respond to a Reuters request for comment for this story.
Iranian President Masoud Pezeshkiyan warned on Monday of "irreversible" consequences in the event of a general war in the Middle East. A US State Department official said that Washington does not agree with Israel's strategy of escalation and wants to reduce tensions.
Underground Arsenal
In what two sources said was an indication of how well-hidden some of Hezbollah's weapons are, rockets were fired Sunday from an area of southern Lebanon that Israel had targeted shortly before, the sources said.
Hezbollah is believed to have an underground arsenal, and last month released footage that appeared to show its fighters driving trucks with rocket launchers through tunnels. The sources did not specify whether the rockets fired on Sunday were launched underground.
If the chain of command is broken, Hezbollah fighters on the front lines are trained to operate in small, independent formations, capable of fighting Israeli forces for extended periods.
Israeli Defense Minister Yoav Galant said that tens of thousands of Hezbollah rockets and ammunition were destroyed on Monday.
The Israeli military claims that long-range cruise missiles, rockets with warheads capable of carrying 100 kg of explosives, short-range rockets and explosive drones were hit.
Reuters could not independently confirm the Israeli army's claims.
Boaz Shapira, a researcher at Alamo, an Israeli organization specializing in Hezbollah, said Israel has yet to target strategic locations such as long-range rockets and drone depots. "I don't think we are even close to finishing this," said Šapira.
Hezbollah is believed to have about 150 rockets in its arsenal, according to a US congressional report. Krieg claims that the most powerful long-range ballistic missiles are stored underground.
Hezbollah has spent years building a network of tunnels that Israel estimates stretches for hundreds of kilometers. The Israeli military said Monday's strikes hit Hezbollah rocket launch sites hidden under houses in southern Lebanon.
Hezbollah maintains that it does not place military infrastructure near civilians, and the group did not issue a statement regarding the aftermath of Monday's attack.
Tunnels
Hezbollah's leader, Nasrallah, said the group's weapons arsenal and tunnel network have expanded since the 2006 war, especially when it comes to precision-guidance systems. Hezbollah officials said the group has used only a small portion of its arsenal in combat over the past year.
Israeli officials said Hezbollah's military infrastructure is tightly linked to the villages and communities of southern Lebanon, with ammunition and rocket launchers stored in homes throughout the area. Israel has been bombing some of these villages for months to reduce Hezbollah's fighting capabilities.
A 2021 Alamo report said Iran and North Korea helped build the tunnel network after the 2006 war.
Israel has already faced challenges trying to eliminate Hamas commanders and autonomous fighting units from the tunnels that run under Gaza.
"It's one of our biggest challenges in Gaza, and it's certainly something we could face in Lebanon," Karmit Valensi, a senior researcher at the Institute for National Security Studies in Tel Aviv, told Reuters.
Andreas Krig added that, unlike Gaza, where the tunnels were mostly dug by hand in sandy soil, the tunnels in Lebanon were dug deep into the mountain rock. "They are far less accessible than in Gaza and even more difficult to destroy."
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