The IDF detected a deep Hamas attack tunnel in recent days, stretching from the southern Gaza Strip into Israel. The discovery was kept under a media ban until Monday.The 30-meter deep shaft was likely dug after the military’s 2014 Operation Protective Edge offensive, according to an IDF assessment, though this has not been verified. A senior security source said a “systematic, intelligence- based, technological, engineering and operational” approach resulted in the finding of the tunnel. “We have to turn this event, of finding a tunnel, into a system, and find more tunnels,” he added.“The challenge is very big. The tunnels are very deep. We have capabilities that do not exist anywhere else in the world. We can detect them, at depths of 30 to 40 meters,” the source said. “It is a very complex process.” He declined to discuss the detection techniques, which remain classified, saying only that “we have developed all sorts of capabilities in recent years, and they have reached the fruition stage.” According to defense sources, before Operation Protective Edge, the defense establishment was able to find tunnels through randomly drilling holes next to each other along the Gaza border.“This [the current discovery] was not random, but the result of following a pattern. It is a technique that identified their tunnel,” the source added.A second defense source said Israel is “in a different place” compared to where it was before the 2014 war when it came to finding tunnels.The defense establishment believes that Hamas is digging several additional attack tunnels, and that these have likely come to within a few meters of the border, but have not yet crossed it.Gazan diggers could be ordered to tunnel under the border when an escalation looks imminent. With Israel’s new detection capabilities in place, however, it remains unclear how worthwhile it is for Hamas to continue to invest millions of shekels and hire thousands of miners for its tunnel networks.Hamas said Monday that a “terror tunnel” extending from the coastal enclave into Israel that the IDF uncovered was but a “drop in a sea of moves” it is preparing against Israel.Hamas’s military wing, the Izzadin Kassam Brigades, said that “after massive criticism [by Israelis] against the enemy’s [Israel’s] military commanders and politicians, and following long months during which they attempted to put an end to the fear prevailing in their country... the enemy announced the discovery of a tunnel east of Rafah this morning.”Disparaging the IDF, the statement specified that “during today’s maneuver, the enemy attempted to imitate Kassam’s operation methods.”The Kassam Brigades tried to sew panic among Israelis, saying that the IDF had not discovered all of the details about the tunnel, and Hamas would release this information “at the right time.”The statement was concluded with the Izzadin Kassam Brigades’ promise that more surprises for the IDF are on the way. “The preparation for war continues in all arenas, and what the enemy uncovered today is but a drop in a sea of moves the resistance has prepared in order to protect its people, free its prisoners and liberate its land.”The IDF’s Gaza Division, which belongs to the Southern Command, has placed counter-tunnel measures – detecting and destroying them – as its No. 1 priority in 2016. Many units, some of them technical, have been engaged in employing overt and covert capabilities as part of the effort.“The tunnels are a very serious threat,” the senior security source said, though he added that they are “not a strategic threat.”“In this case, we proved our ability to identify a deep space and to strike it. We know how to strike it, and this is a huge challenge,” he said.He described a process that fused intelligence, engineering and operational capabilities to locate and destroy the subterranean threat from Gaza. “If we can do this, detect and destroy them, and achieve it without reaching an escalation, that is our set mission.If this does lead to an escalation, it will not deter us either,” the senior security source said.“Our enemy is sophisticated. Hamas is not a group of idiots,” the officer warned. “Hamas draws lessons.” He added that the IDF is “always operating under the assumption that there are more tunnels out there.” The latest shaft is similar to the “family of tunnels” the IDF exposed in Operation Protective Edge, the officer said.Defense Minister Moshe Ya’alon said on Monday, “We have no illusion when it comes to Hamas’s intentions. Even before Operation Protective Edge, during the operation, and of course, after it, we dedicated many efforts – technological, intelligence and operational – to discovering tunnels from the Gaza Strip.”Ya’alon added that throughout the years, Israel discovered “many tunnels,” and that “we are continuing to focus huge efforts toward that. In tunnel detection missions, most of which are hidden from view, the best of the State of Israel’s forces are involved, from the IDF, the Shin Bet, and defense industries.”Tunnel detection is at the top of the defense establishment’s priorities, Ya’alon said.In recent months, at least 10 Hamas tunnels have collapsed, the defense minister said. “Diggers were killed during their work. And now a tunnel has been detected. Nevertheless, we do not delude ourselves that Hamas will learn the lesson and stop doing this, and that it will turn to helping [Gazan civilians] and improving the fabric of life in the Gaza Strip, or tend to the welfare of residents there.”The most recent tunnel collapse occurred Monday on the Sinai-Gaza border. Seven miners are reported missing.Israel is not seeking a confrontation, Ya’alon said, “but if Hamas tries to challenge the State of Israel, or disrupt the lives of Gaza border residents, it will be hit very hard. We will not tolerate such attempts.”The defense minister called on people living near the Strip to “continue with their daily routines,” and urged the remainder of Israeli citizens to “visit the south of the country during the coming holiday.”The State Comptroller on Monday announced that it will publish a major special report on war-making policy during the 2014 Gaza war, including with reference to aspects of the Hamas tunnel threat.The comptroller said that the report would also address the decision- making process and communication between top policymakers and top military commanders.A not yet publicized draft of the report was sent to the prime minister, the defense minister and the IDF chief-of-staff for comment in February.The IDF Spokesman’s Office said that the military uncovered a “terrorist attack tunnel,” adding that it was “neutralized in a controlled manner.”“IDF units are securing, in a broadened manner, the Gaza border region to ensure the safety of residents,” the Spokesman added.“Detecting the terrorist tunnel is the fruit of extensive efforts to defend and thwart [against this threat]... in cooperation with the Shin Bet. These efforts have gone on since the end of Operation Protective Edge,” it said.Hamas dug the tunnel to “carry out attacks in Israeli territory against Israeli civilians and security personnel, and to harm Israeli sovereignty. The IDF will continue to act to locate terrorist tunnels, through the various means that it has at its disposal to thwart terrorism against Israeli civilians,” it added.OC Southern Command, Maj.- Gen. Eyal Zamir, said that finding the tunnel was the result of “continuous, determined and skilled work by our forces.”Maayan Groisman contributed to this report.