Israeli engineers set explosives to destroy a Hamas tunnel in the Gaza Strip on November 7. Photo: Times of Israel

Israel faces many challenges when dealing with Hamas in the tunnel, from determining the entrance to underground operations.

The Israel Defense Forces (IDF) announced that they have destroyed about 130 tunnels in the Gaza Strip since launching a ground operation late last month. However, this is only a small part of the “matrix” of tunnels that Hamas has painstakingly built over the past 30 years, estimated to have a total length of more than 500 km.

Zoran Kusovac, a veteran analyst for Al Jazeera, said that the underground war, the fiercest front in the Gaza Strip, has not yet really begun. “When the war in the tunnels takes place, Israeli casualties will likely increase,” he said.

The IDF previously said 34 Israeli soldiers were killed in the ground operation in the Gaza StripIsraeli forces have so far only besieged Hamas on the ground and called in air strikes to destroy discovered tunnels but have not actually sent forces deep into this underground tunnel network.

According to expert Kusovac, Israeli forces need to identify as many tunnel entrances as possible to gain an advantage in the tunnel battle. This is not a simple task because Hamas is said to have opened tens of thousands of cellar doors in the Gaza Strip.

Videos recently released by Hamas show a number of bunkers camouflaged in bushes, places Israeli soldiers often bypass during operations. The IDF also accused Hamas of placing tunnel entrances in civilian buildings such as schools, hospitals, garages, warehouses, and even landfills.

Some tunnel mouths were buried under rubble after Israeli airstrikes and shelling, making the search more difficult.

However, thanks to the experience gained after the ground war in the Gaza Strip in 2014, the IDF has prepared better options to hunt for Hamas underground bunkers. Thousands of cellar doors in the Gaza Strip were recently discovered by the IDF, thanks to the application of unmanned reconnaissance devices (UAVs) capable of analyzing the movements and recognizing the faces of Hamas gunmen. Some tunnel doors were identified thanks to the informants that Israel placed in the territory.

“I wouldn’t be surprised if Israel already knows the location of half the bunkers in the Gaza Strip,” Kusovac said.

Israeli forces discovered a tunnel entrance inside a house in the Gaza Strip on November 7. Photo: Times of Israel

Israeli forces discovered a tunnel entrance inside a house in the Gaza Strip on November 7. Photo: Times of Israel

According to this expert, tunnels in the Gaza Strip often have many entrances. Unless the IDF discovers all the tunnels and destroys them, Hamas forces can still operate normally underground.

To be able to map the Hamas tunnels and identify all the entrances, Israeli commandos will have to go down the tunnel. Underground positioning devices such as GPS do not work because satellite signals cannot penetrate the soil above. To respond, Israeli commandos can use positioning devices that use magnetic sensors and motion sensors, like the type used for pedometers.

“These sensor devices are often rudimentary and inaccurate, but they are still better than nothing,” Kusovac said.

Once down in the basement, Israeli soldiers will have to use night vision goggles to observe and limit the use of light-emitting devices to avoid detection. They also cannot use radio to communicate like on the ground but must use wired phones to communicate.

To use this phone, Israeli soldiers will have to grope in the tunnel while spreading phone wires, slowing down their movement speed.

Every time they encounter a branch tunnel, they will have to send a group to stay behind to guard to prevent the risk of being attacked from behind by the enemy. When they find a hatch, soldiers must mark the location and relay information to forces on the ground. This force will be compared to finding the entrance outside.

Challenge Israel when fighting in the Hamas tunnels

Members of the al-Qassam Brigades, the armed wing of Hamas, inside a tunnel in the Gaza Strip in August 2014. Photo: Reuters

Israel once revealed that it owns a specialized robot capable of paving the way, detecting paths and sending images to the operator above. However, this robot cannot go up and down stairs or overcome obstacles, so it can only operate on one level of the tunnel. This makes it unable to replace humans in the task of mapping tunnels.

Not only was it time-consuming and labor-intensive, but this task also contained many risks because Hamas forces had likely set up booby traps in most of the tunnels. They are remotely activated or explode spontaneously when they sense light, vibration, noise, movement or changes in CO2 concentration due to the presence of humans.

Hamas also installed many observation devices to monitor the enemy’s movements in the tunnel. These devices operate thanks to a network of cables inside the bunker, but Israeli soldiers cannot arbitrarily cut off any wires they see because some types of booby traps can activate themselves if lost—electricity supply.

This is extremely dangerous because explosions under the tunnel have much greater damage than when they occur on the ground. The fire spread faster and sucked out all the oxygen inside the tunnel, causing those who did not die from the explosion to die from suffocation.

Even if the enemy does not trigger a booby trap, Hamas forces can still light incendiary substances to create explosions inside the tunnels. “This tactic hardly causes damage to the tunnel system, allowing Hamas to use it normally after the enemy is repelled,” Kusovac said.

To cope, Israeli commandos can use gas masks and oxygen tanks, but wearing such bulky equipment can affect their ability to communicate and fight, according to Kusovac.

This expert believes that the IDF will avoid direct combat with Hamas in the tunnel because their technological advantages and weapons are difficult to promote in this environment. Tear gas can be an effective solution to force Hamas gunmen to leave the tunnels.

“Hamas does not appear to have much protective equipment, so any type of tear gas could be highly effective,” Kusovac said, adding that the IDF could also release water to flood the tunnels.

In the event of an underground clash, Israeli forces will not be able to use many types of weapons because they are often too large and cumbersome to use in narrow spaces. Muzzle flash when firing a weapon in the dark can also affect the shooter’s vision, especially when wearing specialized night vision goggles.

Therefore, it is likely that Israeli soldiers will only carry small guns with silencers to limit muzzle flashes during combat.

No matter what weapon is used, the firepower of both sides will be limited because the narrow terrain means that only a maximum of two people can shoot at a time, of which one person must kneel. They cannot use explosive grenades but can still use stun grenades, but there is still a risk of harming their side.

Forces on both sides will be equipped with daggers because close combat in narrow spaces like tunnels is difficult to avoid. Some opinions suggest that Israel could use attack dog teams to fight underground, but Kusovac does not think this is a feasible option.

Challenge Israel when fighting in the Hamas tunnels

“Dogs become very difficult to control when placed in stressful fighting conditions. Some cases show that they can attack their own side due to being affected by light or noise during fighting,” this expert commented.

To completely destroy the tunnel, Israeli forces need to dig deep holes in the walls and ceiling of the tunnel, then place explosives inside to collapse the tunnel’s structure.

“This is a process that requires a lot of time and is not feasible while fighting is happening, so Israel will likely try to eliminate the Hamas fighters first, and then find a way to destroy the tunnel system.” of the enemy,” Kusovac said.

The IDF could also choose to seal the tunnel doors by pouring concrete or using “sponge bombs.” This is a small chemical bomb that can release a large amount of expanding foam and quickly harden. However, this is only a temporary solution, and Israel will still want to eradicate the tunnels, Kusovac said.