As Gaza Crisis Escalates, Some Experts Fear a Hamas ‘Surprise’

Loay Ayyoub for The Washington Post
A rocket launched from Gaza toward Israel. After the Israel attack, Hamas announced that it had used 35 self-detonating drones.

In late 2016, aerospace engineer Mohamed Zouari was sitting in his car in a seaside Tunisian town when a truck screeched to a halt in front of him, blocking his way. Two masked figures walked up to the startled man and raised pistols with long silencers. They fired 20 shots and sped away, police said, leaving the dying Zouari bleeding in the front seat.

It was a professional hit, and suspicions quickly fell on the Israeli intelligence service, Mossad. The Israelis had reasons for wanting Zouari: He was publicly known as a builder of armed drones for the terrorist group Hamas. At the time of his death, the Iranian-trained Zouari had been completing his masterwork, a submersible drone that could be fitted with explosives to attack oil rigs, port facilities and ships at sea.

The assassination ended the career of the Hamas weapons-maker, but Zouari’s prized invention survived, at least in design. Israeli forces spotted and destroyed a similar submersible drone in 2021 as Hamas attempted to launch the vessel from a beach in Gaza. Military experts say Hamas almost certainly has more like it, inside hidden arsenals that may also include other advanced weapons that Hamas has been working for years to acquire.

As the intensity of Gaza war increases, so do the odds that Hamas will unveil a deadly surprise, according to analysts who study the group’s military capabilities. A day after the Oct. 7 terrorist attack against Israel, Hamas announced that it had used 35 self-detonating drones – all of them based on Zouari’s early weapons designs – in the assault they dubbed Operation Al-Aqsa Flood.

The group’s weaponeers also are known to have acquired technology for an array of new weapons, from powerful mines and roadside bombs to precision-guided munitions. Some were developed by Hamas engineers outside Gaza, in most cases with technical assistance from Iran.

Most of the weapons used on Oct. 7 had been seen before. But experts fear that Hamas may be holding a more technologically advanced arsenal in reserve, preferring to deploy them as a response to an Israeli ground assault that its leaders surely knew would be coming.

“It is quite likely that Hamas has capabilities that we haven’t seen yet, but might see later,” said Fabian Hinz, a missiles expert and defense analyst at the Institute for International and Strategic Studies, a British think tank. If Hamas follows the same playbook as its ally Hezbollah – the Iranian-backed group militant that went to war with Israel in 2006 – it may seek to draw in Israeli forces and then strike unexpectedly, perhaps against targets far from the front line, Hinz said.

“The idea is to get to a higher level of escalation,” he said, “and then pull the rabbit out of the hat.”

An official with the Israel Defense Forces declined to speculate about weapons that might be deployed against Israelis in a ground offense in Gaza, saying only, “We have protective systems.”

Hezbollah’s startling new capability in the 2006 war was an anti-ship missile. Israeli intelligence agencies had seen no evidence that Hezbollah was capable of striking naval vessels miles off the coast until July 12 of that year when, in the early hours of intense fighting, a Hezbollah missile struck the INS Hanit, the flagship of the Israeli Navy, killing four crew members.

If Hamas is planning a similar surprise, it could well be an undersea drone similar to the one that Zouari was developing for Hamas more than seven years ago, according to Hinz and other analysts. Or it could be large missile equipped with a precision-guidance system, potentially enabling the group to accurately strike vital infrastructure or military bases many miles away. So far, the thousands of Hamas rockets and missiles fired into Israel have lacked sophisticated guidance packages, Israeli officials say, even though the terrorist group is believed by many experts to have acquired essential technology from Iran or Hezbollah years ago.

Israeli ground troops and vehicles meanwhile could encounter more powerful variations of the deadly roadside bombs Iran-backed groups have been working for nearly two decades to perfect. Earlier this year, leaked U.S. intelligence reports described how Iranian experts were coaching Syria-based militants on crafting an armor-piercing bomb that could slice the steel plating of a battle tank from 75 feet away.

“Israel has invested in heavy armor for their vehicles, but if you have a 500- or 1,000-pound buried bomb in the road, that can flip an armored vehicle or lift a tank off the ground,” said Michael Eisenstadt, director of military and security studies at the Washington Institute for Near East Policy. “That’s not to mention the impact of the blast wave on the crew – even if they survive.”

The powerful bomb described in U.S. intelligence reports was an explosively formed penetrator, or EFP, a more potent version of the improvised explosive devices used by Iranian-backed insurgents in dozens of lethal attacks against American military convoys during the U.S. occupation of Iraq.

A document that was part of the trove of classified materials leaked on the messaging platform Discord said Iran’s elite Quds Force unit was overseeing testing of one such explosive, which reportedly ripped through a tank in a successful trial run conducted in late January in Dumayr, east of Damascus, the Syrian capital. An apparent attempt to use such devices against U.S. forces in Syria was apparently thwarted in late February when three bombs were seized by U.S.-allied Kurdish fighters.

Hamas’s enhanced capabilities across a range of weapons systems stem largely from the support provided by Iran, said current and former U.S. intelligence officials. While there is no hard evidence so far that Tehran directed or approved the Oct. 7 terrorist attacks, Iranian officials are known to have provided high-tech training and know-how to Hamas and its allies as part of the estimated $100 million in military support given to Palestinian groups.

Iran has for years provided prototypes for rockets, missiles and drones used by Hamas and Palestinian Islamic Jihad, a smaller Gaza-based faction that has joined Hamas in battling Israelis. It also helped Hezbollah field tens of thousands of rockets and missiles, many equipped with guidance systems that should allow them to accurately hit distant targets. Similar weapons helped Iranian-backed Houthis rebels in Yemen score direct hits on oil refineries and civilian airports in Saudi Arabia in recent years. On Thursday, a U.S. Navy destroyer in the Red Sea shot down Houthi missiles and drones that Pentagon officials say may have been aimed at targets in Israel.

Using Iranian technology, Hamas has built underground factories capable of mass-producing rockets and drones. Key components, such as explosives and electronic circuitry, is smuggled into the enclave through tunnels or dropped off the Gazan coast by boat, U.S. and Israeli officials say.

While smuggling relatively large objects such as missiles is difficult, the components needed to convert “dumb” rockets into guided precision weapons are small, according to Hinz, one of several analysts who assess that Hamas probably has such weapons. “You wouldn’t even need a backpack to smuggle in the components. You could put them in a fancy handbag,” he said.

Building an underwater drone is a greater challenge, but Hamas has shown itself to be technologically up to the task. The basic design was worked out years ago by Zouari, the aerospace engineer who worked for Hamas inside Gaza before returning to his hometown of Sfax, on the Tunisian coast, to build the prototype.

The prospect of terrorist drones streaking through the coastal waters to blow up Israeli ports and ships appears to have frightened Israeli officials into taking action. No group claimed responsibility for dispatching the team of assassins that killed the engineer just out steps from his house in 2016, but Israeli officials did not refute Hamas claims linking the killing to Mossad. Asked by Israeli reporters to comment about the incident, Avigdor Liberman, the country’s defense minister at the time, said Israel would do whatever was necessary to “protect our interests.” Two Bosnian nationals were later arrested in connection with the crime, although courts have so far refused Tunisia’s request for the suspects’ extradition.

The discovery by Israeli forces of a Hamas underwater drone in 2021 proved that work on the project has continued. The vessel, destroyed by Israeli warplane as it was being launched from a Gaza beach, was capable of carrying about 66 pounds of high explosives, an IDF spokesman said.

Such discoveries have challenged the notion among some Israelis that their superior technology will keep them safe. Early investigations into the Israeli intelligence failures on Oct. 7 suggest that Israeli were lulled in false sense of security because of their belief that the Hamas threat had been largely contained by an elaborate defensive network of border walls, electronic sensors and antimissile systems such as the Iron Dome. Yet, Hamas managed to catch the country’s vaunted defense and military agencies off guard.

“This is the asymmetrical warfare of the 21st century,” said Lenny Ben-David, a former deputy chief of mission for the Israeli Embassy in Washington and an author of several reports on Hamas and its military capabilities. “What we’ve learned is that we will continue to be surprised by things.”