Similar to recently discovered excavations, one tunnel found last year was, after investigations, found to be 1.5 miles (2.4km) long and up to 20m deep, using 800t of concrete and estimated to cost USD 10M.

It was equipped with electricity, and had chambers with provisions to last occupants extended periods of time. Pedal-operated tools were used for excavation.

From early use of tunnels for smuggling restricted materials (weapons, building supplies, and even KFC) past
IDF checkpoints, Hamas moved into more daring territory for its underground activities. Bunker complexes were created to protect commanders, and clandestine routes into Israel to allow the deployment of strike teams have been dug.

It is the latter use which allowed the famous kidnap of an Israeli soldier in 2006, and earlier this month facilitated a mission to infiltrate and attack a kibbutz in the country’s south.

Another recent raid targeted a patrol Jeep and fighters were equipped with tranquilisers.

Investigating one such location on 30 July, IDF soldiers were killed entering a tunnel that had been preemptively booby trapped by Hamas forces. One explosive device was concealed within the tunnel, while a second was in the house above the portal, collapsing the structure.

Since the start of the current Operation

Protective Edge, the IDF claims to have uncovered 23 tunnels with 66 access points. With detection the most important part of the tunnel war for Israel, the Times of Israel newspaper has reported that the IDF considered, but didn’t follow up with procuring the work of Paul Bauman, who holds the position of technical director of geophysics for WorleyParsons’ Canadian business.

Bauman is an expert in below-surface exploration with electrical resistivity tomography (ERT). While it is not foolproof, it is thought a combination

of several techniques including radar, tomography and seismic measuring could go some way to mapping the area’s covert use of underground space.

Fighting in the region has escalated in recent weeks, with over 1,700 Palestinians, and over 50 Israelis having lost their lives at the time of writing.