What we know about the Hezbollah pagers attack

Hezbollah blamed the attack on Israel. The Israel Defense Forces declined to comment on whether it was responsible.

Israel uses sophisticated cyberespionage methods to spy on and track members of the militant groups it opposes, including Hamas and Hezbollah. It has also built a far-ranging surveillance system using facial recognition to monitor Palestinians in the West Bank.

But the scale of such an attack, targeting thousands of Hezbollah members at once by use of their own devices is unprecedented.

How did the pagers explode?

Israeli operatives likely intercepted the pagers somewhere in the supply chain before Hezbollah got them and rigged them with explosives, said Emily Harding, deputy director of the International Security Program at Center for Strategic and International Studies, a Washington think tank.

Videos posted of the attack on social media suggest that the “explosive devices were integrated into the pagers,” N.R. Jenzen-Jones, a weapons and ammunition expert and researcher at Nottingham Trent University, said in a post on X. “The scale suggests a complex supply-chain attack, rather than a scenario in which devices were intercepted and modified in transit.”

Cellphones long ago replaced pagers for most people, but the devices are still widely available. They’re part of the same complex electronics supply chains connecting manufacturers in Asia with resellers all over the world.

“This looks to be perhaps the most extensive physical supply chain attack in history,” said Dmitri Alperovitch, chairman of the Silverado Policy Accelerator, a national security think tank.

Could lithium batteries be responsible?

Modern consumer devices, including some pagers, have lithium ion batteries that can explode or catch on fire if they get too hot or come into direct contact with metals. Lithium batteries as small as a regular Double-A battery can explode and cause burns, said Richard Meier, principal expert with Meier Fire Investigation, who has overseen many investigations into lithium battery fires.

In one case, a small battery exploded in a person’s pocket after coming into contact with loose change, causing severe burns. Lithium batteries that overheat can reach 2,000 degrees Fahrenheit, Meier said. Devices are generally designed to vent this heat, but if they don’t, “the battery can and will explode,” he said.

Some batteries rely on the devices’ own software to regulate their use and temperature, so it is theoretically possible to hack into a pager and trigger its battery to heat to the point that it explodes, Meier said.

At the same time, videos of the attack posted to social media show the pagers exploding instantaneously, rather than catching fire. Overheating lithium batteries sometimes explode, but also catch fire or throw off streams of superheated material in unpredictable ways.

Why were Hezbollah members using pagers?

In July, Reuters reported that Hezbollah had turned to pagers in recent months for communication after banning the use of cellphones from the battlefield, out of concern that Israel could use them to locate and monitor fighters.

Pagers don’t have cameras or microphones, making them less risky for people who are concerned about surveillance, said Harding.

Could Israel have carried out such an attack?

Israel’s cyber-capabilities are well known. The IDF’s Unit 8200, composed of thousands of soldiers, develops technology to collect intelligence and monitor the military’s targets. The unit’s veterans often go on to work at prominent cybersecurity companies or found their own start-ups. Israel has used cellphone data to monitor the movement of people in Gaza during the war.

In 2012, U.S. officials confirmed that the U.S. and Israel had jointly developed a cyberweapon known as Stuxnet that infected industrial control computers around the world as part of an operation to slow down Iran’s nuclear development program.

Private Israeli companies create and sell sophisticated cybersecurity and surveillance software as well. A 2021 investigation by The Washington Post and 16 media partners found that Israeli firm NSO Group had sold military-grade spyware to other governments that used it to infiltrate cellphones used by journalists, politicians and activists.

Rachel Chason in Jerusalem and Ellen Nakashima in Washington contributed to this report.