There's some commentary on that page that says: > Experts are pointing to the fact that the footage of the explosions is not consistent with a battery overheat

There's some commentary on that page that says: > Experts are pointing to the fact that the footage of the explosions is not consistent with a battery overheating. > Early theories are that this was a so called supply chain attack which involved the pagers being tampered with during their manufacture or in transit.