Israel responds to Hamas tunnel warfare

The Telegraph:

‘Sponge bombs’ are Israel’s new secret weapon to block Hamas tunnels

Israel will use novel “sponge bombs” as it fights through the network of Hamas tunnels under Gaza.

The Israel Defense Forces (IDF) has been testing the chemical bombs, which contain no explosives but are used to seal off gaps or tunnel entrances from which fighters may emerge.

The IDF has not commented on the use of the so-called “sponge bombs”, which create a sudden explosion of foam that rapidly expands and then hardens.

Its soldiers were seen deploying the devices during exercises in 2021. The army has set up a mock tunnel system at the Tze’Elim army base near the border with Gaza.

Troops are likely to face a bloody battle through the tunnels known as the “Gaza Metro” when they launch their expected ground invasion. The network is thought to be hundreds of miles long and dense with traps.

It is where Hamas has taken many of the 200 hostages and where its leaders will hope to survive the coming war.
Israeli soldiers blinded mishandling new “bomb”

The “sponge bomb” would prevent soldiers being ambushed as they move further into the network, sealing off gaps through which Hamas could attack.

Contained in a plastic container, the specialist devices have a metal partition separating two liquids. Once this barrier is extracted, the compounds mix as the soldier positions the “bomb” or throws it further ahead.

Specialised teams in the IDF’s engineering corps have been grouped into tunnel reconnaissance units and equipped with ground and aerial sensors, ground penetrating radar and special drilling systems to locate tunnels.

They have also been issued with special equipment to see when underground.

Standard issue night vision goggles need an element of ambient light to work effectively, but with all natural light blocked out when moving underground, troops will rely on thermal technology to see in the total darkness.

Novel radios, optimised for working in the extreme conditions experienced underground, have also been developed.
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Israel may also use robots and drones to help when navigating the tunnels - but so far, there have been difficulties operating these underground.
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US troops had to deal with tunnel warfare in Vietnam.  The Hamas tunnels are lined with concrete making them more bomb resistent.