The Islamist movement has a network of 500 km of underground passages under the Palestinian enclave. Enough to put the Israeli forces in difficulty during their ground offensive, as this maze is so little known.
A city beneath the city. Faced with the advance of the Israeli army, Hamas can count on an underground network of several hundred kilometers. The “Gaza Metro”, as the forces of the Hebrew State call it, houses command rooms, weapons and fuel reserves, caches for terrorists and hostages… Franceinfo explains to you why these sophisticated tunnels, created twenty years ago, constitute an undeniable strategic asset for Hamas and a major challenge for the Israeli army, which claimed on Tuesday November 7 to have penetrated “in the heart” from Gaza City.
“Destroying Hamas means destroying this network of tunnels”the IDF said on the social network. The armed forces of the Jewish state, which regularly communicate on the threat represented by Hamas tunnels, showed on the platform how they could neutralize them using explosives. However, these operations promise to be complicated due to numerous obstacles.
The Israeli army accuses Hamas of exploiting these tunnels for military purposes, under civilian infrastructure such as hospitals, schools and mosques. On Sunday, November 5, the IDF announced, with supporting video, that it had discovered a tunnel entrance in front of the Sheikh Hamad hospital, in the north of the Gaza Strip.
The army also communicated about another establishment, the Indonesian hospital in Gaza, which allegedly concealed “a command center” of Hamas in his basement. A rocket launch pad was reportedly discovered just 75m from the building. “They know full well that if Israel launches an air attack on this launch base, the hospital will be damaged”declared Daniel Hagari, spokesperson for the Israeli army, denouncing “the cynical use of hospitals” by the Palestinian movement. At the end of October, the army already accused Hamas of harboring tunnels under Al-Shifa hospital, the largest hospital in the Palestinian enclave. Accusations denied by the Islamist group.
A tortuous network
It is also likely that a large number of the approximately 240 Hamas hostages, held captive since the October 7 terrorist attacks, are being held underground. Yocheved Lifshitz, 85, a former Israeli hostage released on Monday October 23, was detained in this underground network. “They made them walk several kilometers in the tunnels, on wet ground. It was a huge underground network, like a gigantic spider web of tunnels”, described his daughter Sharone during a press conference. What interest does Hamas have in keeping the hostages in these tunnels? “It’s the most secure space, and it forces the Israeli army to come in and try to rescue them. Hamas has created a series of horrible dilemmas.”, estimates Scott Savitz, engineer at Rand Corporation, a military research center for the American government. Because by destroying the tunnels, the Israeli army also puts the hostages in danger.
In a publication dated October 17, the Modern War Institute at the American military academy West Point discusses a “underground nightmare” of 1,300 galleries of 500 km buried under a cramped territory 41 km long and 6 to 12 km wide. For comparison, the Paris metro has 226 km of tunnels. In this labyrinth of narrow tunnels lined with concrete walls, the command posts sit alongside the weapons and fuel storage rooms, while others house generators. “This is a military base, under a civilian population”summarizes Daphné Richemond-Barak, researcher at the West Point academy and teacher at Reichman University in Herzliya in Israel, on franceinfo.
The latter was able to visit a Hamas tunnel after the 2014 war. “It’s claustrophobic! After 20 minutes, you really want to get out. Now, to find your way back, good luck. It’s a scary place and it’s almost an existential fear in fact”describes the researcher. “The average Hamas tunnel is only two meters high and one meter wide, making it extremely difficult to enter, move around and fight in.”explains John Spencer, the author of the West Point Academy publication on the Hamas tunnels.
“These tunnels are not built in a linear fashion. They are zigzag and on several levels.”
Daphné Richemond-Barak, researcher at West Point Academyon franceinfo
The teacher thus believes that the “Gaza metro” is “much more sophisticated” for example the network of tunnels used by Daesh in Syria and Iraq. According to an Israeli military official interviewed by AFP, the cost of building each kilometer of gallery would amount to $500,000 (around 460,000 euros). How was Hamas able to finance these tunnels? By diverting international aid, assures Harel Shorel, specialist in Palestinian issues at Tel Aviv University (Israel), interviewed by France 2.
A network difficult to destroy
Part of the network was weakened in 2013, when Egypt flooded the smuggling tunnels with seawater and sewage. According to the Egyptian army, nearly 1,400 tunnels were blocked between 2013 and 2014. In 2014, during the “Protective Edge” operation carried out in the Gaza Strip, 34 tunnels, almost half of which led into the territory Israeli, had been destroyed, according to the IDF. In 2021, the army claimed to have destroyed 100 km of tunnels during Operation Guardian of the Walls. Yahya Sinouar, leader of Hamas in Gaza, replied that this operation had damaged only 5% of the “Gaza metro”.
The tunnels don’t just have a defensive function. They can also be used to attack or smuggle contraband goods. One of them allowed Hamas, in 2006, to enter the territory of the Hebrew state to kidnap the Franco-Israeli soldier Gilad Shalit. In the current context of the war in Gaza, these tunnels make it possible to surprise the adversary by attacking them from behind, or by placing explosives under enemy soldiers, explains Scott Savitz. This video published by the Al-Qassam Brigades, the armed wing of Hamas, allegedly shows an assault carried out on November 1 on Israeli tanks from tunnels in the Zeitoun neighborhood, south of Gaza City.
A tricky maze
Are IDF aerial bombardments useful against these tunnels? Not according to Scott Savitz. “It’s very hard to destroy these tunnels from the surface. You need to know where they are, which is not trivial. There are ‘bunker busters’, bombs designed to penetrate targets at depth. But faced with very deep tunnels, it is ineffective”, explains the American engineer. The IDF certainly has the GBU-28 anti-bunker bomb, which can hit targets up to 30 m underground, but some Hamas tunnels are 70 m deep, notes researcher John Spencer.
Breaking into an enemy tunnel isn’t easy either.
“Tunnels always confer tremendous advantages on their occupants over external forces, because the creators have shaped them in their own way.”
Scott Savitz, engineer at Rand Corporationat franceinfo
And to continue: “They know the conditions, they have the ability to place all kinds of threats: ambushes, landmines, traps.” Yahya Sinouar, leader of Hamas in Gaza, confirmed during a speech that he had placed “hundreds of thousands of traps” in these tunnels.
In John Spencer’s view, the IDF is one of the best prepared armies in the world to wage underground warfare. It has specialized units such as the Yahalom unit, dedicated to the search, clearance and destruction of tunnels. This unit notably includes the Samur sub-unit (“weasel” in Hebrew) composed of soldiers trained to enter these tunnels, to destroy them from the inside.
Among the special equipment these units have, ground and aerial sensors to locate tunnels, remote-controlled robots to explore them safely, radios and navigation technologies operating underground and night vision goggles. To seal these tunnels after their destruction, John Spencer also cites several types of explosives and bulldozers.
“No one wins a war with tunnels alone, but it gives a big advantage”summarizes Scott Savitz, who anticipates an Israeli strategy “case by case”. Daphné Richemond-Barak is of the same opinion: “To be able to completely eradicate [ces tunnels]you have to know them all”explains the researcher. “It’s almost insurmountable from a military point of view. It’s possible, but it will never be 100%.” In the opinion of many experts, this “tunnel war” is therefore expected to last.