Israel launched a covert operation against Hezbollah on Tuesday by embedding explosives within a shipment of Taiwanese-made pagers destined for the militant group, The New York Times reported, citing American and other officials briefed on the operation.

The pagers, which Hezbollah had ordered from Gold Apollo, a company based in Taiwan, were reportedly tampered with before reaching Lebanon. Most of the devices were the AR924 model, though other models were included in the shipment. Explosives, weighing just one to two ounces, were implanted near the pager batteries, according to two officials. A remotely triggered switch was also installed to detonate the devices.

At 3:30 p.m. in Lebanon, the pagers received a message that appeared to come from Hezbollah leadership. Instead, the message activated the explosives, causing the devices to detonate. Lebanon’s health minister reported that at least 11 people were killed and more than 2,700 were injured in the attack.

The pagers were programmed to emit a beeping sound for several seconds before exploding, according to three officials familiar with the details. While Hezbollah has accused Israel of orchestrating the attack, the group has provided few details about the operation. Israel, for its part, has not commented or claimed responsibility.

American and other officials, speaking anonymously due to the sensitive nature of the operation, suggested that the attack disrupted Hezbollah’s communications, striking at a vulnerable point in the group's infrastructure.

Independent cybersecurity experts who reviewed footage of the explosions concluded that the blast was likely caused by a type of explosive material. Mikko Hypponen, a cybercrime specialist and adviser to Europol, told The New York Times that "the size and strength of the explosion indicate it was not just the battery."

The shipment of over 3,000 pagers, ordered from Taiwan, had been distributed to Hezbollah members across Lebanon and to their allies in Iran and Syria. The attack only affected pagers that were switched on and receiving messages at the time of the detonation.