Hezbollah vowed to respond to an Israeli attack yesterday that killed several people and wounded thousands across Lebanon, when pagers belonging to members of the Iran-backed group exploded almost simultaneously, revealing a massive security breach and showing the extent of Israeli intelligence.

Among those killed in the explosions was a child, and around 2.800 people were wounded, said the Lebanese Minister of Health Firas Abiad. At least 170 people are in critical condition, he added, although the nature of other injuries is unclear.

This unprecedented attack risks further escalating tensions in the Middle East, which have already been heightened by Israel's war against Hamas in Gaza. This exceptional incident also highlights the vulnerability of Hezbollah, whose communications network has been compromised with deadly consequences, and follows a series of targeted assassinations of its commanders.

CNN has learned that the explosions were the result of a joint operation between Israel's Mossad intelligence service and the Israeli military. Although the Israeli military said it would not comment on the explosions, both Lebanon and Hezbollah blamed Israel for the attack. Iran also blamed, calling it "Israeli terrorism".

Speculation is mounting about how the low-tech wireless communication devices may have been used. The New York Times reported yesterday that Israel had hidden explosives in a batch of pagers ordered by the Taiwanese manufacturer Gold Apollo and intended for Hezbollah. A switch was added to detonate them remotely, the media report said.

The founder and president of "Gold Apollo" told reporters today that the pagers used in the attack were made by a European distributor. Su Ching-kuang said his company has signed an agreement with a distributor to use the Gold Apollo brand.

Videos circulating on social media and in news agencies show powerful explosions in various locations across Lebanon. In one security camera video, a man is seen selecting fruit in a supermarket when the explosion rips his bag to pieces. Witnesses run away after hearing the explosion, as the man falls to the ground, clutching his lower abdomen. After a few seconds, he is heard moaning in pain.

Other videos on social media show scores of wounded people, including at least one child. The wounded were covered in blood, many with injuries to their faces and hands. "This criminal and treacherous enemy will surely receive a just punishment for this sinful attack, both in expected and unexpected ways," Hezbollah threatened last night.

They later declared that their operations against Israel would continue and promised "fierce retribution that awaits the criminal enemy for the carnage it has committed."

The militant group previously confirmed on its Telegram channel that "workers" at various Hezbollah institutions were hit by the blasts, with "a large number" of people injured.

Hezbollah has long emphasized secrecy as a core element of its military strategy, rejecting high-tech devices to avoid infiltration by Israeli and US spyware.

Unlike other non-state actors in the Middle East, Hezbollah units are believed to communicate through an internal communications network. This is seen as one of the key elements of the powerful group, which has long been accused of operating as a state within a state.

Iran's ambassador to Lebanon, Mojtaba Amman, was among those wounded in Beirut, along with two embassy staff, according to Iranian state media. Aman has a superficial injury and is under observation at the hospital, state news agency IRNA reported, citing his wife.

Lebanese Prime Minister Najib Mikati condemned the attack as a "serious violation of Lebanese sovereignty and a crime by all standards" at a cabinet meeting yesterday, according to state news agency NNA.

The Israeli military, which has been exchanging attacks with Hezbollah since the start of the Gaza war in October last year, said in a statement after the explosions that there was no change in advice for Israeli civilians. "The public is asked to remain on high alert, and any change in policy will be updated immediately," the statement said.

Explosives placed in pagers

A wave of explosions hit several areas in Lebanon, particularly the southern suburbs of Beirut, according to the Lebanese Internal Security Forces.

NNA reported that "hacked" pagers exploded in the towns of Ali Al-Nahri and Riaq in the central Bekaa Valley, resulting in significant injuries. The locations are Hezbollah strongholds.

CNN previously reported that the pagers that exploded were purchased by Hezbollah in recent months, according to a Lebanese security source. The devices detonated simultaneously after receiving a message on Tuesday afternoon.

Eyewitnesses described the carnage in Beirut after the explosions.

"We were surprised that there were so many people covered in blood, especially children," said Michelle Hodegem, a woman who worked as a paramedic in Beirut. "Many families ran to the hospital with their children in their arms."

The explosions resulted in scenes of "disaster" in many of the affected locations, she added. "The most severe cases were of people who were very close to the explosion," she said.

"We were surprised that there were so many people ... there was blood on the roads and people were being taken to the hospital in ambulances. But we didn't know what was happening," said one witness, who did not want to be named for security reasons.

The witness told CNN that he had gone to the hospital to visit a friend who was carrying one of the pagers when it exploded.

“This device was not only in the hands of people belonging to [Hezbollah], but in the hands of all people. "There were people working in the security field who were using that device and they were also injured," he said.

David Kennedy, a former intelligence analyst for the US National Security Agency, told CNN that the explosions seen in the videos shared online appeared to be "too large for this to be a remote and direct hack that would overload the pager and caused an explosion of a lithium battery."

"It is more likely that Israel had human operatives ... in Hezbollah ... The pagers would be embedded with explosives and would probably only be activated when a certain message was received," he said.

"The complexity required to achieve this is incredible. That would require very different intelligence components and execution. Human intelligence (HUMINT) would be the main method used to achieve this, along with supply chain interception in order to make modifications to the pagers."

Kim Ghattas, a Lebanese journalist and contributor to Atlantic magazine, told CNN that Hezbollah recently "went low-tech" in an effort to prevent the assassination of more of its operatives. In a speech in February, Hezbollah chief Hassan Nasrallah urged his fighters to throw away their cellphones, saying: "turn it off, bury it, put it in an iron chest and lock it up."

Pagers made by a European distributor

More details emerged today about how Israeli intelligence may have engineered the unprecedented attack.

Hsu, the founder of pager maker Gold Apollo, said its European distributor, later named BAC in a company statement, established a relationship with the Taiwanese firm about three years ago.

Initially, the European company imported only Gold Apollo pagers and communication products, he said. Later, the company told Gold Apollo they wanted to make their own pager and asked for the right to use the Taiwanese firm's brand, he said.

Hsu said Gold Apollo encountered at least one anomaly in its dealings with the distributor, citing a jury transfer that took a long time to clear up.

Taiwan has no record of Gold Apollo pagers being delivered to Lebanon or the Middle East, a senior Taiwanese security official told CNN today. Gold Apollo shipped about 260.000 pagers from Taiwan from January 2022 to August 2024, mostly to the United States and Australia, the official said.

Lebanese authorities urged citizens with pagers to throw them away, warned hospitals to be on "high alert" and asked health workers to report to work immediately to help with the "large number of injured people".

The explosions come after Israel's security cabinet voted on Monday to add another military objective to the ongoing conflict with Hamas and Hezbollah: ensuring the safe return of residents from communities along the Lebanese border to their homes.

"Israel will continue to act to implement this goal," Prime Minister Benjamin Netanyahu's office said Monday.

After nearly a year of cross-border firefights between Hezbollah and Israel, tens of thousands of people have been displaced from their homes in southern Lebanon and northern Israel.

The US was "not involved" in the series of pager blasts in Lebanon and was "not aware" of any attack in advance, according to a State Department spokesman.

Following the attacks, European airlines Air France and Lufthansa suspended flights to Tel Aviv until at least Thursday "due to the security situation at the local level".

Air France said it was also suspending flights to Beirut until Thursday amid fears of an escalation in the region.