Tunnel Wars: Israel's Gaza Assault Lays Ground for Lebanon Clash

Israel's operation in the Gaza Strip is raging above and below ground as its troops hunt for Hamas leaders and uncover a sprawling network of tunnels even more extensive than once thought.

"The army knew that there was a big infrastructure of underground tunnels in Gaza, they didn't realize the extent," Amir Avivi—the founder and chairman of Israel Defense and Security Forum and a former Israel Defense Forces (IDF) senior commander—told Newsweek during a Jerusalem Press Club briefing on Wednesday. "Everything is done underground. And when it's done underground, it's very difficult to understand exactly what's going on."

Tunnel warfare has been central to Israel's operation within Gaza. As Israel seeks a concrete victory in the Strip, military lessons learned there may prove useful in any renewed conflict with the Lebanese Hezbollah militia on Israel's northern border. Tensions have been high along that frontier since October, with constant exchanges of fire. "Hezbollah is operating in similar ways as Hamas," Avivi said.

Israel's Gaza offensive has now killed more than 30,000 Palestinians, per figures reported by the Associated Press. The operation has precipitated a humanitarian crisis, with a quarter of Gaza's 2.3 million people now facing starvation and 80 percent having fled their homes, accordingto the United Nations.

In a statement sent to Newsweek following a recent trip to Gaza, Norwegian Refugee Council Secretary General Jan Egeland described "a civilian population engulfed by destruction, desperation and despair. Famine is a growing threat here, as millions of trapped people face a nightmare of violence and starvation."

Israel's offensive began in the north around Gaza City. It has since turned south, with Khan Younis as the major objective. But despite large areas of IDF control, fierce fighting and high civilian casualties continue all over the besieged territory.

On Thursday, the Associated Press reported that IDF soldiers fired on a crowd of civilians waiting for humanitarian aid in Gaza City. Palestinian authorities said at least 100 people were killed.

An IDF spokesperson told Newsweek that during the entry of humanitarian aid trucks, "Gazan residents surrounded the trucks, and looted the supplies being delivered. During the incident, dozens of Gazans were injured as a result of pushing and trampling. The incident is under review."

War Underground

As in previous incursions into Gaza, the hunt for militant tunnels is a top priority for the IDF. The sophisticated complexes have traditionally been used to house leaders in relative safety, store militant weapons caches, launch attacks into Israel and smuggle arms and other equipment into the blockaded coastal Strip.

The IDF said the tunnels played a role in the October 7 infiltration attack into Israel, in which some 1,200 people were killed and hundreds taken back to Gaza as hostages. More than 100 remain unaccounted for. The IDF death toll from its Gaza operation is 242.

Israeli forces have been using a variety of methods to locate and destroy the tunnels, even including pumping water from the Mediterranean to flood the passages. Avivi suggested Israeli intelligence and military leaders have been surprised by how many tunnels militants have built.

"Unfortunately, both Shin Bet [Israel's internal security service] and the army didn't develop human resources inside the Gaza Strip in a way that they can get really the full picture of what's going on," he said.

"They relied a lot on technological intelligence, and that was not enough. Hamas adapted technology; they used less phones, computers, internet, they operated underground in a way that created many, many gaps to the Israeli intelligence."

"Now, most of the intelligence we're getting on the ground is coming from the two sources the army almost completely disregarded. One is human intelligence, and the other one is the gathering of everything that we're finding in the houses and inside the tunnels—whether it's computers, maps, documents—that are analyzed."

"We understood that if we want to win the war, we need to also fight underground," Avivi said. The lessons being learned, he added, will be valuable to any IDF troops fighting in a future conflict with Hezbollah.

The Tehran-aligned Lebanese group is "operating according to Iranian doctrine," Avivi said, "and the Iranians understand that the big advantage of Israel and the U.S. is the air force and intelligence."

"The way they're overcoming this is by really putting everything underground," he added. "The only way to really deal with this threat is with the ground forces conquering the area, arriving to these tunnels, fighting in them, and destroying them."

Tal Beeri, the director of research at the Alma Research and Education Center, told The Times of Israel in January that Hezbollah has created a "Land of the Tunnels" under its southern Lebanon strongholds.

Though Israel is aware of some, "we're not sure that we discovered everything, we don't know," Avivi said. "We don't have a technological barrier in the north the way we have now in the south."

"There will always be tactical surprises, but the army prepared for a very, very long time for a possible war in Lebanon."

Gaza's 'Last Refuge'

Israel has razed parts of Gaza and killed thousands of militants, according to figures from the IDF and from Hamas itself. But Hamas' two most important leaders—Gaza head Yahya Sinwar and military commander Mohammed Deif—remain unaccounted for, and the group's armed units are still in the fight, even if degraded.

Israeli Prime Minister Benjamin Netanyahu's plan to "eradicate" Hamas was always ambitious when dealing with a de-centralized, grassroots, guerrilla movement operating throughout—and beyond—the Strip.

Victory for Israel is nebulous. Plans to retain full military control over Gaza and the occupied West Bank, and to continue its block on Palestinian statehood are winning Israel few friends abroad.

Foreign outrage will be piqued if the IDF launches its planned operation into Rafah, a settlement on the border with Egypt which has become the "last refuge" for nearly 1 million Palestinians fleeing the fighting. The border area is known as the Philadelphi Corridor, and tunnels running underneath it form vital militant smuggling routes.

Israeli leaders have expressed their intention to enter Rafah and occupy the corridor, despite protests from Egypt, the U.S., several other nations, the United Nations, and a host of NGOs.

"When we go into Rafah, this is going to be in the south the decisive battle that will destroy Hamas as a governmental and military entity," Avivi said. "I don't see any scenario where Israel is not going into Rafah."

"You cannot deal with the tunnels that are coming from Egypt without taking over," he said.