what intrigued me most, looking at the photos, was that the explosion from inside unit 501 blew off only the exterior walls of only that unit, and so cleanly, with hardly any jagged edges, and the exterior walls of the units beside, above, and below it are hardly damaged except for shattered glass windows and the like. it didn’t make sense, unless, unless, aha, the walls are pre-fab?!? googled it and, yes! “precast wall” it’s called. this is how they’re made, and this is how they’re “installed.”
so, i wonder what industry people are saying. mabuti na lang that those walls were precast, otherwise they would not have been blown away so easily? had those walls been made of poured concrete (buhos) with rebars and all, they would have been thicker, maybe they would not have been blown away, and damage to the interior would have been greater? maybe the ceiling and floor and inner walls would have been first to give way, and casualties would have been from inside the building? unless of course that explosion was directed at, and meant to blow off, those walls. but why?
so yes, we need to find out what and who caused that explosion. and, certainly, whether precast walls are safe, or should passers-by beware?