To destroy the Hamas tunnels, the Israeli army is said to have developed a device that uses a nearly indestructible expanding foam that expands and solidifies to seal the underground passages.
Following the Hamas terrorist attack, the Israeli army launched a ground offensive in the center of Gaza City. This is just one phase of this war, which is now being fought underground. The IDF’s goal is to disable this labyrinth of tunnels.
This network, described as an “underground nightmare” by the Modern War Institute, a unit of the American military academy West Point, would consist of thousands of galleries at a depth of 40 to 50 meters that, when strung together, could reach a total distance of 500 kilometers.
The tunnels listed by the Israeli army in the Gaza Strip in 2021. – BFMTV
A true underground city nicknamed the “Gaza Metro,” this network of secret infrastructure hides bunkers, command centers and warehouses (food, fuel, weapons, etc.) designed to protect and supply Hamas militants. They would also be used for missile attacks.
A kind of expanding foam
A specialized Israeli unit was formed to explore them using technological tools (drones, sensors, radars, thermal imaging systems or through-wall vision systems, etc.). But to make them permanently unusable, the army is relying on a more rustic system. According to the British media The Telegraph, the underground passages will be destroyed using sponge bombs.
These devices are bombs in name only. They do not cause explosions that could cause collateral damage, but instead release a type of expansive foam that can fill spaces of tens of cubic meters.
These sponge bombs are based on a chemical process. Two liquid components separated by a metal partition are placed in plastic bags. These containers are thrown into the tunnels and, when mixed, immediately release a foam that permanently clogs all the cavities, both those intended for circulation and those necessary for ventilation.
Make the tunnels permanently unusable
In a filmed test we can see the effect of these sponge bombs in a replica of the Gaza tunnels. They cause a tidal wave of foam that, once spread, expands and solidifies in the same way as the expanding foam used in construction. This product is non-flammable and resistant to water and chemicals. Reusing these tunnels, if still possible, would require drilling.
In recent years, Israel has tried to destroy the tunnels by blowing them up or using bulldozers, but Hamas has managed to rebuild them each time by reinforcing them.
Currently, the Israeli military has not confirmed the use of these sponge bombs. The risk is that the hostages who would be found in the tunnels, as well as the civilians who would have sought refuge there to protect themselves from bombing, or the hostages housed in the hospitals above the tunnels, would be condemned definitively.