Other comments here are suggesting it was more likely a real explosive put in as part of a physical supply chain attack. Anyone able to say which is more plausible?
> The official said some people felt the pagers heat up and disposed of them before they burst.
Sounds more like a battery explosion, but it's way too early to tell.
While the Note 7 exploded with quite a bit of force, they never caused injuries like these, and the Note 7 likely had much bigger battery than these pagers had.
We won't know for sure until the devices have been examined.