The Hamas tunnels in Gaza have been in the news since Hamas attacked Israel on October 7, 2023. The labyrinth of these tunnels reportedly extends to some 500 kms. Israel has uncovered about 50 Hamas tunnels till now. These include tunnels under hospitals in Gaza, especially under the Al Shifa Hospital. Israel has recently also reported discovering Hamas tunnels underneath Gaza City headquarters of the UN agency for Palestinian refugees. According to media reports, some Hamas tunnels cross into Egypt, allowing Hamas leaders to enter or leave Gaza at will.

Israel has been suffering the menace of Hamas tunnels from direction of the Gaza Strip; both offensive and defensive – terror attacks and to deter Israeli Defence Forces (IDF) when they enter the Gaza Strip. In 2014, Israel launched ground operation in Gaza to neutralize 32 Hamas tunnels, 14 of which crossed into Israel. IDF then estimated Hamas spent around $30 million to $90 million, using 600,000 tonnes of concrete to build 36 tunnels, some individually costing $3 million.

The labyrinth of Hamas tunnels reportedly extends to some 500 kms, with tunnels discovered under hospitals in Gaza and the Gaza City headquarters of the UN agency for Palestinian refugees.

It was reported in these columns on November 8, 2017, that Israeli engineers were working on a NIS (New Israel Shekel) 3 billion Gaza border fence that runs above and below ground and includes an underground concrete barrier armed with cameras and sensors due for completion by early 2019. Despite the fence, the October 7, 2023, Hamas attack on Israel was very successful.

Most significantly, the IDF has recently captured two Chinese engineers in the HAMAS tunnels – both from China's People's Liberation Army (PLA). China has not only been providing military training to Hamas but Mohammad Deif, military head of Hamas, lived in China for many years and is married to two Chinese Muslim women. Apparently, the October 7, 2023 attack on Israel was masterminded by China, not Iran, as assumed by the West and Israel. This is revealed in the article 'China is the hand behind Hamas attack on Israel' authored by Joyeeta Basu, published on May 19.

Media reports from November 2011 revealed that China has built a massive tunnel network, dubbed the "Underground Great Wall," to hide its increasingly sophisticated missile and nuclear arsenal.

Tunnels have been used in warfare for centuries - Assyrians used tunnels in the 9th century BC. Romans and Persians tunneled under barricades and walls to enter cities and fortresses. Tunnels were used in world wars as well. The Cu Chi tunnels in Vietnam at multiple levels spread over some 200 sq km, enabled resistance forces to fight American forces for seven years, eventually forcing withdrawal of the US forces, The US bombed the tunnels and used chemicals and defoliants but could not win the war.

Between the 1960s-1980s, North Korea reportedly dug 103 tunnels under the heavily guarded Demilitarised Zone (DMZ) for conducting surprise underground invasion of South Korea, the first tunnel was discovered in 1974 by a South Korean Army patrol that saw steam rising from the ground and heard underground explosions. Based on intelligence reports, Republic of Korea (ROK) forces searched for more suspected tunnels in the area around Cholwon, near the center of the DMZ, hiring a Korean mineral firm to conduct the drilling. However, a second tunnel was discovered only in 1975. The 3rd tunnel was discovered on October 17, 1978. Two of these tunnels discovered are large enough to push a brigade-sized force across in one hour with small vehicles.

Between the 1960s and 1980s, North Korea reportedly dug 103 tunnels under the heavily guarded Demilitarised Zone (DMZ) to conduct surprise underground invasions of South Korea, with the first tunnel discovered in 1974.

Media reports of November 2011 said China has built a massive tunnel network (thousands of miles) to hide the increasingly sophisticated missile and nuclear arsenal – dubbed "Underground Great Wall" by the Chinese. A detailed study over three years by Georgetown University students made this discovery, their suspicions raised, noticing thousands of radiation technicians were rushing to Sichuan after a devastating earthquake in 2008, and pictures of strangely collapsed hills amid speculation that the caved-in tunnels in the area held nuclear weapons.

China has been undertaking extensive tunneling in Pakistan occupied Kashmir, ostensibly for hydel projects and other China-Pakistan-Economic Corridor (CPEC) related projects. However, many of these tunnels are assumed to be housing missiles, some of which may be nuclear as well. Reports of the PLA tunneling in Eastern Ladakh have also been coming intermittently after the Chinese invasion in 2020.

The Indian Army has deployed tunnel defences to pre-empt any further transgressions by the PLA in Eastern Ladakh according to media reports. China used tunnel warfare against Japan in the second Sino-Japanese war. The PLA has tunnel shelters for aircraft at Lhasa, and the underground pens for submarines in Hainan Islands. The latest is that China is developing tunnels under the reclaimed islands in the South China Sea (SCS).

Pakistan has used tunnels to infiltrate terrorists across the Line of Control (LoC) and the International Border (IB), as well as for smuggling weapons, explosives, and narcotics, with many tunnels still undiscovered despite surveillance efforts.

Over the years, Pakistan has used tunnels to infiltrate terrorists both across the Line of Control (LoC) and the International Border (IB). These tunnels are also being used for smuggling weapons, explosives and narcotics. Such tunnels are discovered intermittently by our security forces but many more may exist despite physical and technological surveillance. The problem gets more acute when there is connivance on the Indian side to assist drugs-cum-arms smugglers or a combination of smugglers and terrorists, including camouflaging the mouth of the tunnel.

Finally, our focus must include not only a comprehensive surveillance system but also a tunnel detection system. In addition to researching and developing indigenous technology for efficient tunnel detection systems using all our national resources, this must also be a priority issue in India-Israel cooperation. As important is the need to develop a tunneling concept at the national level – both for defensive and pro-active operations; including paying Pakistan in the same coin.