Thought sabotaging enemy equipment to explode isn't.
Had this been a bunch of Russian or Wagner Group radio equipment exploding because they had been rigged by Ukraine, it wouldn't be a war crime - combatants don't stop being valid targets even if they are on leave and are at fault of endangering the civil population, possibly themselves causing a war crime by effectively using civilians as human shields in the process.
Pagers are civilian objects, they're categorically different from radio equipment because they can be used by civilians.
Furthermore, these exploded in civilian structures among the civilian population. Pagers blew up inside people's cars while driving down the highway. They blew up on grocery stores. They blew up children.
A pager isn’t “enemy equipment” in the same way a missile or a gun is. There were literally cell phone stores exploding in Lebanon. A 9-year-old girl died. This is 100% a fucking war crime. If someone kills a member of your family do you get to booby-trap the stove in their house so the kids get their faces melted off?
A booby trap is defined as “any device designed or adapted to kill or injure, and which functions unexpectedly when a person disturbs or approaches an apparently harmless object,” according to Article 7 of a 1996 adaptation of the Convention on Certain Conventional Weapons, which Israel has adopted. The protocol prohibits booby traps “or other devices in the form of apparently harmless portable objects which are specifically designed and constructed to contain explosive material.”
The prohibition is presumably intended to make it less likely that a civilian or other uninvolved person will get injured or killed by one of these seemingly harmless objects. If you're booby-trapping military equipment or military facilities then that's not a problem, civilians wouldn't be using those.
When you are a paramilitary organization, the line between what is military equipment and what isn't gets quite blurry. Especially when they weren't really "boobytrapped", they were turned into remote explosives and did nothing until explicitly triggered.