Israel played a role in manufacturing the pagers that exploded among Hezbollah operatives this week, ABC News reported, citing a US intelligence source.

The report said that this type of “supply chain interdiction” operation had been in the works for at least 15 years.

The CIA has been hesitant to employ such tactics due to the high risk of collateral damage to innocent people, the source added.

The operation involved shell companies, with multiple layers of Israeli intelligence officers and their assets posing as part of a legitimate business. The company in question manufactured the pagers, and at least some individuals involved in the process were unaware of who they were truly working for, according to the report.

Israel’s involvement in the pager manufacturing was initially reported by The New York Times.

Sources indicated that the pagers were rigged with one to two ounces of explosives and a remote trigger switch designed to detonate the devices.

Over the past two days, a series of explosions in Lebanon – remotely triggered through pagers or walkie-talkies embedded with explosives – has resulted in the deaths of at least 37 people and left nearly 3,000 injured, according to Lebanese Health Minister Firass Abyad.

In a speech on Thursday, Hezbollah leader Hassan Nasrallah said that the group’s senior leadership had older pagers, not the new ones used in the attack, which were reportedly shipped within the last six months. Hezbollah has since initiated a full investigation into the explosions.

“Not all of the pagers had been distributed and some of them were turned off,” Nasrallah said.

“Over two days, the enemy wanted to kill at least 5,000 people. ... The enemy knew that the pager devices numbered 4,000,” he added.