Israeli Prime Minister Benjamin Netanyahu has told residents of Gaza border communities that the army is "probably on the verge of finding a solution" to end the threat of tunnel attacks by Hamas and other Palestinian militant groups.
Israel recently indicated it was in the process of testing equipment to detect tunnels near the border, but remains tight-lipped about the technology being used. The government is under pressure to respond to the tunnel threat, following claims by Hamas that they have substantially rebuilt their tunnel network following the significant damage inflicted on it by Israel during the 2014 war, and reports from Israelis living near the border that they can hear digging under their houses.
Israel's new tunnel-fighting technology — dubbed the "underground iron dome," in homage to the missile defense system that since its 2012 installation has destroyed near 90 percent of rockets and mortars fired at Israel from Gaza — is thought to have undergone initial tests in August last year in unused sewage networks beneath Tel Aviv. According to local media reports it will likely use sensors that gather information below the ground and that will then be analyzed using algorithms.
Contacted by VICE News, Israel's Ministry of Defense said that "due to the sensitivity of the issue… as a rule, the Ministry does not comment on tunnel detection technology."
According to a recent report on Israeli Channel 2, more than a billion shekels ($250 million) have been spent by the Israeli army trying to thwart tunnel attacks since 2004. But despite the large investments, previous attempts to develop detection systems in 2005 and 2006 stalled after equipment failed test runs. Previous plans to build an underground wall were also ditched due to high costs and concerns about its durability in the sandy desert soil.
For Israel time is now of the essence. In recent weeks Hamas, the Islamist militant group that controls the marooned 223 square mile Gaza Strip, has bragged that it is rebuilding its underground network after the Israeli army destroyed more than 30 tunnels during a bloody 50-day war in 2014.
Speaking at the funeral of seven men who died while excavating a tunnel in the Southern Gaza Strip in late January, Ismail Haniyeh, leader of Hamas in Gaza, said that Palestinian militants had already dug twice the number of tunnels as Viet Cong guerrillas did during their 19-year war with America in Vietnam. "The Al-Aqsa Martyrs' Brigades are digging tunnels to defend Gaza and turn it into a launch pad for all of Palestine," he added. As much as a third of the pre-war tunnel network is already thought to have been rebuilt.
Tunnel warfare is not a new phenomenon in the troubled border area. In 2006 two Israeli soldiers were killed by militants who emerged from a tunnel near Kerem Shalom kibbutz. A third soldier, Gilad Shalit, was kidnapped and held captive for five years before being exchanged for more than 1,000 Palestinian prisoners held in Israeli jails.
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During the 2014 war at least four separate attacks were launched on Israeli army outposts via tunnels by Palestinian militants, with an anti-tank weapon used to kill four Israeli soldiers in one of the assaults.
Hamas' incentive to up the ante underground may now be even greater now as the Iron Dome missile defense system means most rockets fired from the Strip are now destroyed mid-air. Additionally, Hamas has struggled to replenish its arsenal since the last war after Egypt demolished thousands of smuggling tunnels in the Sinai that were previously used to bring weapons into the Strip.
Netanyahu's Wednesday evening meeting with kibbutz leaders, some of whose communities lie just meters from the border, follows a series of reports from people living in the area that they can hear digging beneath their houses.
Israel's army says that investigations in the area have not revealed any tunnels, but locals remain fearful. A recent amateur video shot by residents living on the Israeli side of the northern Gaza border appears to capture a series of explosions and battle cries coming from a Hamas post just a few hundred meters away.
Adding to those concerns, a draft report given to senior Israeli government officials at the beginning of February warned that there remained "gaps and failures, some of them serious, in preparations to meet the threat of the tunnels and in dealing with them." A response to the findings is expected in coming weeks.
Follow Harriet Salem on Twitter: @HarrietSalem
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