The Washington Post revealed Wednesday that although Israel has not publicly claimed responsibility for the bombing attacks in Lebanon, the Israelis informed the United States of the attack after it occurred through intelligence channels, according to two American officials who spoke to the newspaper on condition of anonymity to discuss sensitive matters.

The officials said the Israelis did not alert Washington about the details of the attack before it happened.

At least 14 people were killed and more than 450 injured in Wednesday’s explosions, Lebanon’s health ministry said in an update. The blasts occurred across Lebanon, according to the Lebanese Civil Defense agency. Tuesday’s pager explosions killed 12 people — including at least two children — and injured thousands.

Thousands of pagers used by the Hezbollah group exploded across Lebanon at 3:30 p.m. Tuesday, wounding at least 2,800 people and killing at least 12, according to Lebanese health officials. The apparent massive attack raised immediate questions about how the smaller devices could have exploded at the same time.

Hezbollah blamed Israel for the attack, while the Israeli military declined to comment.

On Wednesday, a second round of explosions killed 20 and injured at least 450. The attack appears to have affected a wider range of electronic devices, including radios and fingerprint scanners, according to reports.

Israel uses advanced cyber espionage techniques/supplied by the CIA to spy extensively in the region, especially on Hamas and Hezbollah. It has also built a long-range surveillance system using facial recognition to monitor Palestinians in the West Bank.

Emily Harding, deputy director of the international security program at the Center for Strategic and International Studies (CSIS), a Washington think tank, said Israeli agents may have intercepted the pagers somewhere in the supply chain before Hezbollah received them, and planted explosives in them.

Videos of the attack posted on social media indicate that “explosive devices were integrated into pagers.”

“The scale points to a sophisticated attack on the supply chain, not a scenario where devices were intercepted and modified in transit,” Jensen Jones, director of Armament Research Services, a weapons research firm, said in a post on X.

Cell phones have long since replaced pagers for most people, but the devices are still widely available. They’re part of the same complex electronics supply chains that connect manufacturers in Asia to distributors around the world.

“This appears to be perhaps the most comprehensive physical attack on a supply chain in history,” Dmitri Alperovitch, president of the Silverado Policy Accelerator, a national security think tank, told the newspaper.

But where did these pagers come from?

According to the newspaper, two photos posted on social media in the aftermath of the attack show the charred and crumbling back panels of the pagers with the word “GOLD” written in text above the model number “AR-9.” The text design matches the text on the back of the “AR-924” pager model made by Gold Apollo Co., which uses a lithium battery.

Based in Taiwan, Gold Apollo is one of the world's leading pager manufacturers.

Gold Apollo said in a statement Wednesday that it did not manufacture the AR-924 pagers that media reports say were used in the attack. It said a company called BAC in Budapest, Hungary, that is authorized to use the Gold Apollo brand “handled the entire process,” including manufacturing and assembly.

Taiwan's Ministry of Economy said in a separate statement earlier Wednesday that it had contacted Gold Apollo, which "questioned whether the product was indeed theirs after reviewing media reports and photos, and judged that the pager may have been tampered with after it was exported."

Gold Apollo has exported 260,000 pagers since 2022 through last month, including nearly 41,000 this year alone, according to ministry data. Most of them were exported to Europe and the United States, the ministry said, and there were no records of direct exports to Lebanon.

It is noteworthy that last July, Reuters reported that Hezbollah had resorted to pagers in recent months to communicate after the use of mobile phones was banned from the battlefield for fear that Israel would use them to locate and monitor fighters.

Pagers do not have cameras or microphones, making them less risky for people who are concerned about surveillance.

What happened in the second round of explosions on Wednesday?

Little is known yet about the explosions that killed 20 people and injured 450 across Lebanon on Wednesday.

The country's state news agency attributed some of the explosions to two-way radios. Lebanon's civil defense said some of Wednesday's incidents were caused by the explosion of "radiophones and fingerprint scanners."

Israel’s cyber capabilities are highly advanced, with the IDF’s Unit 8200, which consists of thousands of soldiers, developing technology to gather intelligence and monitor military targets. Retirees and discharges from the unit often go on to work at prominent cybersecurity firms or start their own startups. Israel used cellphone data to monitor people’s movements in Gaza during the war, experts say.

Experts say that the Mossad operates primarily based on the capabilities of the Central Intelligence Agency (CIA), as well as the British spy agency, MI-5, and the French and German intelligence services.

Israeli military and spy agencies have assassinated Palestinians remotely for decades, with technology playing a major role in many of them.

In 1996, Hamas’s chief bombmaker, Yahya Ayyash, was killed when he responded to a rigged cellphone, possibly as part of an operation by Israeli agents who were relatives of Ayyash, The Washington Post reported. In 2012, U.S. officials confirmed that the United States and Israel had jointly developed a cyberweapon known as Stuxnet aimed at slowing Iran’s nuclear program. The weapon inadvertently infected industrial control computers around the world.

Private Israeli companies also create and sell sophisticated cybersecurity and surveillance software. A 2021 investigation by The Washington Post and 16 media partners found that the Israeli company NSO Group sold military-grade spyware to other governments, which used it to hack the cellphones of journalists, politicians and activists.

However, Tal Mimran, academic director of the International Law Forum at Hebrew University and a former legal adviser to the Israel Defense Forces, told the newspaper that the attack was unprecedented and raised new legal questions about Israel's compliance with international law.

“The pager attack is a new type of attack; we haven’t seen that,” Mimran said. “Were they able to properly assess who would be hit by the attack? How many casualties could be considered collateral damage?”

Could lithium batteries be responsible?

Modern electronic devices, including some pagers, contain lithium-ion batteries that can explode or catch fire if they get too hot or come into direct contact with metal. However, a lithium battery is unlikely to be the cause of Tuesday's explosions, experts say.

Small lithium batteries, such as a regular AA battery, can explode and cause burns, Richard Meier, lead expert at Meier Fire Investigation, who has overseen numerous investigations into lithium battery fires, told the newspaper. In one case, a small battery exploded in a person’s pocket after coming into contact with coins, causing severe burns.

Lithium batteries that overheat can reach 2,000 degrees Fahrenheit, Meyer said. Devices are generally designed to vent that heat, but if they don’t, “the battery can and will explode,” he said.

Some batteries rely on special hardware software to regulate their usage and temperature, so it's theoretically possible to hack a pager and cause its battery to heat up to the point of exploding, Meyer said.

However, Taiwan's Ministry of Economy said in a statement Wednesday that Gold Apollo said the battery inside its pager is the size of a standard AA battery "without the possibility of causing an explosion that could result in injuries."

Meanwhile, videos of the attack posted on social media show the pagers exploding instantly, rather than catching fire. Overheated lithium batteries sometimes explode, but they also catch fire or belch out superheated material in unpredictable ways.

“I’ve seen enough lithium battery fires to know that what we’re seeing in the videos posted is not consistent with a battery fire,” said Jake Williams, a security researcher and vice president of research and development at Hunter Strategy, a security consulting firm. “The electrochemistry in cheap batteries simply doesn’t support them all blowing up in such a short period of time as has been observed.”

Instead, the explosives may have been placed inside the batteries themselves, Williams said.