Since these were all new pagers and since Hezbollah had told their members to stop carrying cell phones I think it was easily some one (you can fill in the blanks) added something to the pagers in the supply chain and so Hezbollah was SOL when they took the shipment.

I doubt it would be that hard to add some sort of software that could be signaled to trigger thermal runaway. We already have an issue with it in EVs and I want to say the Galexy Note 9 form years ago had the same issue.