After three failed attempts in 2006, Israel successfully assassinated the elusive Hezbollah leader through the efforts of Unit 8200 and the Intelligence Directorate (Aman), following a major shift in tactics, according to reports.

The assassination comes from a change of approach from Israeli intelligence which has now transformed the face of the decades-long conflict with Iran’s most powerful proxy after its top ranks have been shattered by two weeks of targeted attacks across Lebanon.

The Financial Times reported that Israel has relied on exceptional intelligence in recent months, beginning with the July 30 assassination of Fuad Shukr, a key aide to Hezbollah leader Hassan Nasrallah.

Officials told the newspaper that there had been a large-scale reorientation of Israel’s intelligence-gathering efforts on Hezbollah after the surprising failure of its far more powerful military to deliver a knockout blow against the militant group in 2006, or even to eliminate its senior leadership, including Nasrallah.

“For the next two decades, Israel’s sophisticated signals intelligence Unit 8200, and its military intelligence directorate, called Aman, mined vast amounts of data to map out the fast-growing militia in Israel’s 'northern arena,'” the paper wrote.

Speaking to Iran International, an Israeli official said that Israel is now working fast before the intervention of the US can stand in the way of its blitzing the group.

“There has to be a major amount of damage done, and quickly, before the US starts to step up pressure for a truce,” he said, speaking on condition of anonymity.

“We don’t want a repeat of Gaza where our hands are tied, limiting the success of our operations and in the end, lengthening the war.”

He said the killing of Nasrallah also marked a political change for Israel, which had in recent years acted more cautiously on the killing of the group's leader, treating him as "more like a head of state". But now, the gloves are off.

Since October 8, Hezbollah has launched over 8,000 projectiles towards Israel in allegiance with Hamas in Gaza’s atrocities of October 7. The invasion saw thousands of Iran-backed Hamas militia invade Israel killing at least 1,100 and taking over 250 hostages to Gaza, 101 of whom remain there. In Israel, 63,000 civilians have since been displaced.

Since the pager explosions which saw around 1,500 Hezbollah operatives taken out of action in Beirut, Israel has gone full force, with troops now on the ground as the country vows to create safety on its northern border in a bid to return home the residents now spread around the country.

Another Israeli official told Iran International that there is a “limited incursion” underway but did not give details beyond the fact special forces are there to dismantle key military targets in the area meant to have been demilitarized under 2006's UN Resolution 1701, a resolution Hezbollah has since continued to breach.

Speaking to the FT, Miri Eisin, a former senior intelligence officer, said Israeli intelligence had “widened its aperture to view the entirety of Hezbollah, looking beyond just its military wing to its political ambitions and growing connections with Iran’s Revolutionary Guards and Nasrallah’s relationship with Syria’s President Bashar al-Assad”.

It has taken 40 years for Israel to get such an upper hand, having seen the group through this time as a “terror army”. Changing this approach, Eisin told the FT that Israel was forced to study the Iran-backed militia with the same eyes as it had the likes of the Syrian army. The Syrian war for which Hezbollah lent its troops, offered the chance to see the group in a more revealing light.

The FT said that “while Hezbollah’s fighters were battle hardened in Syria’s bloody war, the militant group’s forces had grown to keep pace with the drawn-out conflict. That recruitment also left them more vulnerable to Israeli spies placing agents or looking for would-be defectors.”

According to Randa Slim, a program director at the Middle East Institute in Washington, “Syria was the beginning of the expansion of Hezbollah …. That [war] weakened their internal control mechanisms and opened the door for infiltration on a big level.”

The war in Syria also “created a fountain of data, much of it publicly available for Israel’s spies — and their algorithms — to digest”, the report noted.

Obituaries, regularly used by Hezbollah for its martyrs, were one of those vitally revealing tools, offering insights such as where the fighter was from, where he was killed, and his circle of friends posting the news on social media. Funerals also offered the chance to draw senior leaders out of the shadows, even if briefly.

Quoting a former high-ranking Lebanese politician in Beirut, the FT said the penetration of Hezbollah by Israeli or US intelligence was “the price of their support for Assad”.

“They had to reveal themselves in Syria,” he said, where the secretive group suddenly had to stay in touch and share information with the notoriously corrupt Syrian intelligence service, or with Russian intelligence services, who were regularly monitored by the Americans.

Hezbollah blew up Shin Bet’s headquarters in Tyre not once but twice in the early years of Israel’s occupation of southern Lebanon. At one point in the late 1990s, Israel realized that Hezbollah was hijacking its then-unencrypted drone broadcasts, learning about the Israel Defense Forces’ own targets and methods, according to two people familiar with the issue.

Israel’s technical expertise also saw it take advantage of the likes of spy satellites, sophisticated drones and cyber-hacking capabilities that turn mobile phones into listening devices.

Israeli news outlet Ynet said that as Israel began to close in on Hezbollah, the first military intelligence used cyber technology and electronic intelligence gathering, mostly by the IDF's 8200 unit. Then the military gathered visual intelligence that could identify precise coordinates and locations and, finally, the military's 504 unit gathered information from human sources.

Intelligence agency Mossad likely laid the foundations for the entire effort in operations, Ynet said, and the details of which will likely never be revealed as Israel has a tight 50-year non disclosure rule on security information, much of which, even is locked beyond that.

Mossad has a long history of agents on the ground in Lebanon such as the high-profile case of Erika Chambers, a Mossad operative who was one of the people behind the 1979 assassination of Ali Hassan Salameh, a high-ranking official in the Palestine Liberation Organization.

Salameh was a founding member of Black September, the militant group responsible for orchestrating the attack that killed 11 Israeli athletes at the 1972 Munich Olympics. Chambers had entered Lebanon posing as a British charity worker and lived in an apartment overlooking a car park used by Salameh. Eventually, that lookout post would see her detonate the bomb that killed him in 1979, planted on his car by another operative, before she left the country soon after.

Today, Unit 9900, which writes algorithms that sift through terabytes of visual images to find the slightest changes, has also been key, wrote the FT, its work to identify an improvised explosive device by a roadside, a vent over a tunnel or the sudden addition of a concrete reinforcement, hinting at a bunker.

The unit identifies an operative, feeding daily patterns of movements into a vast database of information, siphoned off from devices that could include family phones, or his smart car’s odometer. These can be identified from sources as disparate as a drone flying overhead, from a hacked CCTV camera feed that he happens to pass by and even from his voice captured on the microphone of a modern TV’s remote control, according to several Israeli officials speaking to the FT.

The huge bank of information has allowed Israel to take out of action the top echelons of the group and shock the world in the wake of the pager and walkie-talkie operation in which explosives were planted in the group's communications devices just 10 days before the leader of the group was killed. In between, nearly all the group’s top commanders had been hit, along with a wealth of military infrastructure.

Now, as the Lebanese militia stands in disarray and Israel continues to pound it hard so there is no room to regroup, the Jewish state is simultaneously going hard on Iran’s Yemeni proxy, the Houthis, to make sure they are clear of the consequences of trying to step into the breach.