6 Questions About the Deadly Exploding Pager Attacks in Lebanon, Answered

When thousands of pagers and other wireless devices simultaneously exploded across Lebanon and parts of Syria this week, killing at least 15 people and injuring thousands more, it exposed what one Hezbollah official described as the “biggest security breach” the Iran-backed militant group has experienced in nearly a year of war with Israel. In a period replete with violent attacks across the region—from Israel’s bombardment of the Gaza Strip to the targeted assassinations of militant leaders in Iran and Lebanon—this was perhaps the most sophisticated and daring one yet.

Hezbollah confirmed that eight of its fighters were killed in the blasts taking place on Tuesday, according to the BBC. Further such explosions, this time involving two-way radios, were reported on Wednesday. Civilians haven’t been spared from the onslaught. At least two children were killed in Tuesday’s blasts, according to the country’s health minister, and thousands of others were wounded by them, some critically. Iran’s ambassador to Lebanon lost an eye as a result of one of the blasts, according to the New York Times.

Officials in the U.S. and elsewhere have left little doubt as to who might be responsible. Hezbollah and Lebanese officials quickly pointed to Israel, which in addition to waging its ongoing war with Hamas in Gaza has also been exchanging near daily blows with Hezbollah across its northern border with Lebanon since Oct. 7. Earlier this week, the Israeli government announced it was expanding its war aims to include the return of its northern residents who were evacuated from towns along the country’s northern frontier in the immediate aftermath of Oct. 7—a goal that the country’s defense minister Yoav Gallant said would be achieved through “military action.” Days earlier, Lebanese residents on the other side of the border received Israeli military leaflets ordering them to leave the area. The Israeli military has since confirmed that their distribution as an “unauthorized action,” and said that no evacuation is underway.

Still, expert observers warn that this attack, and any retaliation that might follow it, could raise the prospect of a wider war breaking out. Here are six of the biggest questions—and answers—that remain.

How were the explosions triggered?

Hezbollah’s widespread use of pagers—hardly considered a high-tech form of communication by most standards—was primarily a security precaution. The militant group had reportedly ordered its members to forego using mobile phones earlier this year due to concerns that they could be more easily tracked. In their place they were given AR-924 pagers, thousands of which were sourced from a Taiwan-based brand called Gold Apollo. Although the company confirmed it had licensed the use of its brand for these pagers, it declined playing any role in their manufacturing, which it said was done by the Budapest-based firm called BAC Consulting.

Footage from one of the blasts—which TIME was unable to independently verify, but which was deemed credible by the BBC—showed the moment one of these pagers exploded, emitting smoke and causing the person who appeared to be carrying it to fall to the floor.

Experts who spoke with TIME say that this wasn’t a cyberattack. Rather, it was likely the result of an infiltration in the supply chain, which makes how the pagers were manufactured and who was involved all the more critical. “The explosions were likely triggered by pre-implanted explosives, possibly activated via a radio signal, as simple as the paging system itself,” says Lukasz Olejnik, an independent researcher and consultant in cybersecurity and privacy. “The supply chain was likely compromised at some point, either in the factory or during delivery.”

While such an operation would have been difficult to execute, it isn’t beyond the capabilities of a country like Israel. “Israel is obviously still the master of intelligence in the region,” Andreas Krieg, an associate professor for security studies at King’s College London, tells TIME, noting that “it has a network of intelligence and information collection that is unparalleled.”

What is Israel saying about it?

Israel has a long history of pulling off complex attacks of the kind seen in Lebanon. But as with the recent assassination of Hamas leader Ismail Haniyeh in Iran, it rarely takes responsibility for them. When TIME inquired about Israel’s involvement in the pager explosions, an Israeli military spokesperson declined to confirm or deny whether the country was behind the attack, offering only a two-word response: “no comment.”

But experts say that all obvious signs point to Israeli involvement. “No one else is benefiting from it, but Israel, in terms of paralyzing Hezbollah,” says Krieg, noting that the militant group has been the most strategic threat to Israel for at least the past three decades. “There are loads of people who don’t like Hezbollah in the region, including Arab countries,” he adds, “but none of them have the capability to actually do something as sophisticated as this.”

Why now?

There could be any number of reasons for why Israel would opt to launch this attack now. One theory, attributed to senior intelligence sources and reported by Al Monitor, was that the compromised status of the pagers was at risk of being imminently discovered. Another is that Israel perhaps hoped the attack would act as a deterrent following recent revelations that the country’s security service foiled an attempt by Hezbollah to assassinate a former senior Israeli security official using a remotely detonated explosive device.

There’s also the possibility that Israel, having made moving its displaced population back to their homes in the north of Israel among its war aims, wanted to pressure Hezbollah into moving its forces away from the nearby Israel-Lebanon border.

While some observers fear that the attack could have been initiated as a prelude to a wider Israeli military incursion in Lebanon, Krieg says such an escalation would be in neither party’s interests, recent comments from the Israeli defense minister notwithstanding. “This paralysis of [Hezbollah] being unable to communicate effectively with one another is certainly something that could be a preparation, a first step, of such an operation,” he says. “But I don’t think that’s likely.”

Will Hezbollah retaliate?

Hezbollah pledged on Wednesday that it will continue its military operations against Israel in order to “support Gaza,” and warned that Israel will face a “difficult reckoning” as a result of the pager attack, which it called a “massacre.” The armed group’s leader, Hassan Nasrallah, is expected to deliver a speech addressing the attack on Thursday.

How are governments around the world reacting?

A State Department spokesperson, who declined to comment on suspicions that the attacks were carried out by Israel, confirmed that the U.S. had no prior knowledge of the attack, telling reporters on Tuesday that Washington was neither aware nor involved with the operation.

“That’s probably true because I think the [Biden] administration would try and talk them out of it, because they would say it’s escalatory,” Michael Allen, the former National Security Council director for President George W. Bush, tells TIME.

Across the Atlantic, the E.U.’s foreign policy chief Josep Borrel condemned the attacks in a statement, warning that they “endanger the security and stability of Lebanon, and increase the risk of escalation in the region.” He notably did not mention Israel in the statement, opting instead to urge all stakeholders to “avert an all-out war.”

The Iranian government, which backs and sponsors Hezbollah, condemned the attack as a “terrorist act.”

Does this attack constitute a war crime?

While the attack may have targeted pagers used by Hezbollah, that doesn’t necessarily mean that those in possession of them were armed militants. “Hezbollah is obviously the fighting wing, but Hezbollah is [also] a political party, it’s a charity organization, it’s a civil societal movement as well,” says Krieg. “And so this pager system would have been distributed among civilians as well—people who are not fighters, who are not contributing to the war effort, and they were targeted as well.”

It’s precisely for this reason that the use of booby traps are prohibited under international law. “The use of an explosive device whose exact location could not be reliably known would be unlawfully indiscriminate, using a means of attack that could not be directed at a specific military target and as a result would strike military targets and civilians without distinction,” Lama Fakih, the Beirut-based Middle East and North Africa director at Human Rights Watch, said in a statement. “

“Simultaneous targeting of thousands of individuals, whether civilians or members of armed groups, without knowledge as to who was in possession of the targeted devices, their location and their surroundings at the time of the attack, violates international human rights law and, to the extent applicable, international humanitarian law,” Volker Turk, the U.N.’s High Commissioner for Human Rights, said in a statement on Wednesday, adding that those who ordered and carried out the attacks “must be held to account.”