Both Wiens and MG said a supply-chain attack in which a remote-triggered explosive was surreptitiously placed into the pagers before they were distributed is more likely. There is precedent for this: in 1996, Israel put a bomb inside of a cell phone and used it to kill Yahya Ayyash, who was then a bomb maker for Hamas.
Sounds like one of the things mentioned in the Edward Snowden leaks
We live in a gross reality