TEL AVIV, Israel — For the fourth time in three months, Israel employed what is being called here its “steel dome” to detect and destroy a cross-border tunnel from the Gaza Strip.

Inspired by the Israeli Iron Dome, which combines radar, a discriminating battle management system and kinetic interceptors against short-range rockets and other cross-border threats from the air, the so-called steel dome is a multilayered system of new technologies, tactics and procedures aimed at denying militants from Hamas and Gaza-based terror organizations the ability to attack Israel from underground.

The latest demonstration of the new system came in the early morning hours of Jan. 14, when the Israel Air Force — supported by ground forces from the Israel Defense Forces (IDF) Southern Command — detected and destroyed a tunnel that extended nearly a kilometer within southern Gaza, traversed some 200 meters under Israel’s border, and continued about 400 meters into neighboring Egypt.

“The tunnel was located using combined technological, intelligence and operational capabilities,” the Israeli military noted in its Jan. 14 statement. “Locating these tunnels is part of a wide-scale defensive effort led by the IDF and Southern Command.”

In an interview to the Arab-language, U.S.-based satellite television station Alhurra, Maj. Gen. Yoav Mordechai, coordinator of Israeli government activities in the West Bank and Gaza, indicated that Israel has detected additional cross-border tunnels and warned Gazans working in or near them that they, too, would be destroyed.

“Just like there’s Iron Dome for [threats coming from] the air, there’s a technological umbrella of steel underground,” Mordechai said. “I want to send a message to everyone who is digging or gets too close to the tunnels: As you’ve seen… these tunnels bring only death.”

Since late October, Israel has employed ground- and air-based detection capabilities that not only locate the tunnel, but provide Israeli authorities with clearer indication of their route.

In addition to the new detection capabilities and means of destroying the tunnels, Israel is constructing a sensor-fused, underground barrier on its side of the border at an estimated cost of some $800 million, or $11 million for each kilometer its 65-kilometer border with the Gaza Strip.

That physical barrier is scheduled for completion by the end of next year.

Opall-Rome is Israel bureau chief for Defense News. She has been covering U.S.-Israel strategic cooperation, Mideast security and missile defense since May 1988. She lives north of Tel Aviv. Visit her website at