I do wish everyone would stop with this notion that the batteries were part of the explosions, unless as trigger voltage. The brisance alone tells you this was NOT a battery event. Look at batteries gone bad in small devices. Burns are what you get. A well sealed device will expand until it pops the case. Even were they pagers made of metal and well sealed, the pressure rise from an overheating battery would just pop the weakest seem, not shatter them. .
half battery half RDX ?